GRB 030329

B.A. Peterson and P.A. Price (RSAA, ANU) reports:

We have observed the error-circle of GRB 030329 with the SSO 40-inch
telescope in R-band.  We identify a source that is not present on archival
images at approximate coordinates:

	RA: 10:44:49.5    Dec: +21:31:23    (J2000)

This position is preliminary, with an estimated error of 5 arcsec.

Further observations are planned.

This message may be cited.

K. Torii (RIKEN) report:

 The entire error region of GRB 030329 (HETE trigger 2652) was
observed by the automated system at RIKEN (0.25-m f/6.8 reflector
equipped with unfiltered CCD AP6E). The observatin started at 2003
Mar. 29 12:52:09 UT and 60-s intergration is repeated.

 We find a new bright source at position (R.A., Dec.)  = (10 44 50.0,
+21 31 18) (J2000) (preliminary values with a formal error of 6
arcseconds in each coordinate). The object is about 13 mag (USNO-A2.0
red magnitude).

===

P.A. Price and B.A. Peterson (RSAA, ANU) report:

A refined position for the optical afterglow candidate of GRB 030329 is:

	RA: 10:44:50.0   Dec: 21:31:17.8   (J2000)

with an estimated error of 0.5 arcsec in each axis.

We estimate the afterglow candidate to be R ~ 12.4 mag (!!!).

This message may be cited.

P.A. Price (RSAA, ANU) reports:

Identification of the afterglow of GRB 030329 was performed through
clouds, with thunderstorms surrounding the mountain.  Consequently, it
will not be possible to obtain a spectrum of this bright afterglow from
Australia.  Perth observatory is also experiencing thunderstorms.  We
encourage observations by Northern observatories to track the afterglow
lightcurve.

M. Uemura (Kyoto University) reports:

We have started observations of the field of GRB 030329 at 12:53:41
UT, and confirmed the bright afterglow candidate reported in GCN 1985
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and 1986
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 .  We use 30-cm and 25-cm SC telescopes and unfiltered CCDs at
Kyoto, Japan.

In this one hour observation, our perliminary analysis revealed a
rapid fading of the object.   From 12:53:41 UT to 13:51:01, the object
faded about 0.53 mag, which establishes that the bright candidate is
a genuine optical afterglow of GRB 030329.

M. Uemura (Kyoto U.), H. Yamaoka (Kyushu U.), R. Ishioka, and T. Kato
(Kyoto U.) report on behalf of VSNET-GRB collaboration:

  The precise position for the optical afterglow candidate of GRB
030329 (GCN 1985
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 , 1986
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 , 1987
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 , 1689
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 ) was derived from Kyoto images (GCN
1689
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 ) as (with mean error of measurements of nine images):

    R.A.= 10h44m50s.030 +/- 0s.005,  Decl. = +21d31'18".15 +/- 0".07.

  On the DSS 2 B, R, and I images, there is no distinct source down to
the limiting magnitudes, which indicates the parent galaxy is more
than 8-9 mag dimmer of the OT at 76 minutes after explosion.

This message may be cited.

Rykoff, E. S. and Smith, D. A. on behalf of the ROTSE collaboration report:

We have observed the full error box of GRB 030329 (HETE trigger 2652), 
using the ROTSE-3A 0.45 meter telescope at Siding Springs Observatory, 
Australia, starting March 29, 13:05:19 UT (1.46 hours after the burst). 
  Due to partly cloudy skies, our first usable image was taken at 
13:08:45 UT.  We initiated a sequence of 90 one-minute exposures, 
interrupted by a brief spell of light rain.

We identify the bright counterpart reported by Price (1985) and Torii 
(GCN 1986
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 ), at the following coordinates:

   RA: 10 44 50.0  Dec: 21:31:17.8

Some of our detections (unfiltered, calibrated to USNO A2.0 R-band) are:

   UT (start)   Mag (USNO R-band)
   13:08:48     12.88 +/- 0.01
   13:19:15     12.96 +/- 0.02
   13:35:25     13.11 +/- 0.01
   15:34:38     13.90 +/- 0.02
   15:45:16     14.05 +/- 0.03

We continued to follow the transient until it dropped below our 
elevation cut.

A preliminary ROTSE lightcurve can be found at:
   http://www.rotse.net/transients/grb030329/grb030329_lc0.ps
Please note that our magnitude errors fluctuated as clouds drifted 
through the field of view.

Marshall, F.E. and Swank, J.H. (NASA/GSFC) report:

RXTE detected the X-ray afterglow of GRB 030329
(HETE trigger 2652) during a 27 minute observation
that began about 4h51m after the burst at 16:28 UT 
on March 29 . The flux was about 1.4e-10 ergs/s/cm**2 
in the 2-10 keV band or about 0.007 times as bright as the Crab
Nebula. This is one of the brightest afterglows ever
detected with RXTE. The spectrum is well fit by a power law
model with a photon index of 2.0 and an upper limit
on absorption of 1e22 Nh/cm**2.
The X-ray flux was about 20% lower during
a second observation starting at 17:32 UT.

This message may be cited.

R. Vanderspek, G. Crew, J. Doty, J. Villasenor, G. Monnelly, N. Butler,
T. Cline, J.G. Jernigan, A. Levine, F. Martel, E. Morgan, G. Prigozhin,
G. Azzibrouck, J. Braga, R. Manchanda, and G. Pizzichini, on behalf of
the HETE Operations and HETE Optical-SXC Teams;

G. Ricker, J-L Atteia, N. Kawai, D. Lamb, and S. Woosley on behalf of
the HETE Science Team;

T. Donaghy, M. Suzuki, Y. Shirasaki, C. Graziani, M. Matsuoka, T.
Tamagawa, K. Torii, T. Sakamoto, A. Yoshida, E. Fenimore, M. Galassi,
T. Tavenner, Y. Nakagawa, D. Takahashi, R. Satoh, and Y. Urata, on
behalf of the HETE WXM Team;

M. Boer, J-F Olive, J-P Dezalay, C.  Barraud and K. Hurley on behalf
of the HETE FREGATE Team;

write:

At 11:37:14.67 UTC (41834.67 s UT) on 29 Mar 2003, the HETE FREGATE,
WXM, and SXC instruments detected event H2652, a long, extremely
bright GRB.

The burst triggered FREGATE in the 6-120 keV energy band.  The burst
occurred outside of the effective FOV of the WXM Y-camera.  Ground
analysis of the SXC data produced a localization that was reported in a
GCN Notice at 12:50:24 UT, 73 minutes after the burst.  The SXC ground
localization SNR was 20.  Further ground analysis of the SXC data has
provided an SXC localization that can be expressed as a 90% confidence
circle that is 2 arcminutes in radius and is centered at

SXC-Ground:   RA = +10h 44m 50s, Dec = +21d 30' 54" (J2000).

The SXC localization is dominated by systematic errors, which are
larger than usual because the burst occurred at the edge of the SXC
FOV.  (The error circle radius of 2 arcminutes reported in the GCN
Notice for H2652 did not include the larger systematic errors.)

Ground analysis of the WXM data produced a WXM localization.  The WXM
ground localization SNR is > 20.  The WXM localization can be expressed
as a 90% confidence rectangle that is 12 arcminutes in width and 2.25
degrees in length.  The center of the rectangle lies at

WXM-Ground:   RA = +10h 44m 24.7, Dec = +23d 20' 20" (J2000),

and its corners lie at

RA = +10h 44m 39.6s, Dec = +23d 29' 20",
RA = +10h 43m 53.5s, Dec = +23d 26' 35",
RA = +10h 44m 09.8s, Dec = +21d 11' 38",
RA = +10h 44m 55.9s, Dec = +21d 14' 17" (J2000).

The width of the WXM localization is dominated by systematic errors,
which are larger than usual because the burst occurred at the edge of
the WXM FOV.  The WXM localization is a long, narrow strip because the
burst occurred at the edge of the WXM FOV in a region of the sky that
would have been viewed by the YB-camera, which is not operational.

The burst duration in the 30-400 keV band was > 25 s. The fluence  of
the burst was ~1 x 10-4 ergs cm-2 and the peak flux over 1.2 s was > 7
x 10-6 ergs cm-2 s-1 (i.e., > 100 x Crab flux) in the same energy band.

A light curve and skymap for GRB030329 is provided at the following URL:

http://space.mit.edu/HETE/Bursts/GRB030329

[GCN OPS NOTE (29mar03): The "...on 28 Mar 2003,..." in the first line
was corrected to "...on 29 Mar 2003,...".]

GRB030329: Upper limits from recent and historical observations.

W. M. Wood-Vasey, P. Nugent, and B. C. Lee, Lawrence Berkeley National
Laboratory, using images obtained by R. Bambery, S. Pravdo, M. Hicks,
and K. Lawrence (Near-Earth Asteroid Tracking project, Jet Propulsion
Laboratory), report recent and historical upper limits for the optical
transient for GRB 20030329 (GCN #1985
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 , 1986
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 , 1987
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 ) using the position
of Uemura et. al (GCN #1949
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 ) from images taken with the Palomar Oschin
1.2-m and Haleakala MSSS 1.2-m telescopes during the previous two
years:
 
                           Limiting Unfiltered Mag                  
UT Date                          ( @ S/N = 3)          Telescope
--------------------------------------------------------------------
2001 Mar 13.60, 13.61              [ 17.58            Haleakala
2002 Jan  8.46,  8.47,  8.49       [ 20.31            Haleakala
2002 Jan 14.44, 14.45, 14.46       [ 20.26            Haleakala
2002 Jan 21.46, 21.47, 21.48       [ 21.66              Palomar
2002 Feb  3.54,  3.55,  3.57       [ 20.86              Palomar
2002 Feb 13.56, 13.57              [ 18.96              Palomar
2002 Apr  1.27,  1.29,  1.31       [ 21.57              Palomar
2003 Jan 18.50, 18.52, 18.54       [ 20.84              Palomar
2003 Feb 23.50, 23.51, 23.52       [ 20.54            Haleakala
2003 Mar  1.51,  1.52,  1.53       [ 19.89            Haleakala
2003 Mar 23.13, 23.15, 23.17       [ 21.61              Palomar

Magnitudes are calibration against 300 USNO-A V1.0 R-band stars in
the 0.25 sq. degree field of the images.

A co-addition of these images shows nothing at this location to a
combined limiting magnitude of 22.28 (S/N = 3).

The co-addition is available at:

http://supernova.lbl.gov/~wwoodvas/GRB/#GRB20030329

This message may be cited.

A. Gal-Yam, E. O. Ofek, D. Polishook and E.M. Leibowitz 
(Wise observatory, TAU) report:

We are observing the OT of GRB 030329 (Peterson & Price, GCN 1985
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 ) 
using the Wise observatory 1m telescope + SITe CCD camera, starting 
March 29, 17:15 UT (5.6 hours after the burst). Large number 
of 300 s B, 120 s V and 120 s R-band frames are being obtained under 
highly variable conditions, with passing clouds.

We detect the OT on numerous B, V and R-band images. A rough calibration
using nearby bright USNO A-1 stars gives R~14.3 and B~15 for the OT. We
can also estimate the decline rate to be about 0.3 mag/hour in the R-band,
from the first two hours of data. Further data acquisition and analysis 
are underway.

S. Klose, C. Hoegner, J. Greiner (Thueringer Landessternwarte Tautenburg)

report:


We observed the field of GRB 030329 (HETE trigger #2652) with the
Tautenburg Schmidt telescope equipped with the prime focus CCD camera
(2k x 2k). Inspite of terrible weather conditions the afterglow
discovered by Peterson & Price (GCN 1985
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 ) and Torii (GCN 1986
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 ) is
detected in R.

Based on a comparison with the DSS2 red we can only provide a very
rough estimate of the R-band magnitude of the afterglow. The
brightness of the source is approximately R=14.8 +/- 0.5 mag. We do not
believe that we can improve the accuracy of the photometry
substantially. The quality of the images is really very bad. This
information should nevertheless help observers to plan further
observations.

R. Burenin, D. Denissenko, M. Pavlinsky, R. Sunyaev, O. Terekhov,
A. Tkachenko (IKI); Z. Aslan, K. Uluc, I. Khamitov (TUG); U. Kiziloglu,
A. Alpar, A. Baykal (METU); I. Bikmaev, N. Sakhibullin, V. Suleymanov (KSU)
report:

Error box of GRB030329 (HETE Trigger #2652) was observed with 1.5-m
Russian-Turkish Telescope RTT150 at Bakyrlytepe (TUBITAK National
Observatory, Turkey) started at Mar 29.744 UT, appr. 6 hours after the burst.

We confirm the presence of the optical transient (OT) reported by Peterson
and Price (GCN 1985
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 ). In the beginning of our run the afterglow appear to
have the following magnitudes: B=14.99, V=14.46, R=14.12, I=13.60, and is
fading at a rate appr. 0.18 mag per hour in every filter. At 29.794 the OT
has magnitudes: B=15.19, V=14.65, R=14.34, I=13.82. We will continue our
observations as long as it will be possible.

The absolute fluxes will be calibrated more accurately. The light curves
will follow.

This message may be cited.

ITLE: GCN GRB OBSERVATION REPORT

V. Lipunov, A.Krylov, V.Kornilov, G.Borisov, D.Kuvshinov, A.Belinski,
I.Chilingarian, M.Kuznetsov,  S.Potanin, V.Vitrischak, G.Antipov

Sternberg Astronomical Institute, Alexsandr Krylov Observatory, Moscow

We are observing the OT of GRB 030329 in R-band with MASTER system
(280 mm, http://observ.pereplet.ru). We began observations at 17:15UT
(~5h30m after GRB time).
Optical source (about 13.6 in R) was detected at the position given
in Circ 1985 in the beginning of observations. At 20:20UT (~8h40m after
GRB
time) magnitude became more than one magnitude fainter and it was about
14.8 in R. The OT seems to become fainter very slowly.
At present we have about 100 images of the OT. These images are
being processed.

These are preliminary results.

C. Bartolini, A. Guarnieri, A. Piccioni (Bologna University), 
G. Gavazzi (Milano-Bicocca University), R. Gualandi (Bologna 
Astronomical Observatory) and G. Pizzichini (IASF-CNR Bologna) 
report:

UBVRI photometry, for a total of 13 frames, of GRB030329 has
been obtained from March 29.8090 to 29.8139 with the 152 cm 
Loiano telescope.
Data analysis is in progress.

A finding chart in R light can be retrieved by sftp using
hostname : ermione.bo.astro.it
username: publicGRB
password: GRB_bo

S. Klose, C. Hoegner (Thueringer Landessternwarte Tautenburg),
J. Greiner (MPE Garching)

report:


We forgot to mention that our reported R-band data point refers to an
observing run which was performed 19:50 - 20:00 UT.

S.K. apologizes for this mistake.

V.Rumyantsev, E.Pavlenko, Y.Efimov, K.Antoniuk, O.Antoniuk, N.Primak (CrAO)
and A.Pozanenko
(IKI) report:

We have observed the  GRB030329 (HETE #2652) and OT  of the GRB found  by
B.A. Peterson and P.A. Price (GCN 1985
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 ) with Cassegrain 38-cm telescope of
CrAO.
Several 180 sec. exposures of  R (Johnson) filter were obtained.
The photometry of the OT in  respect to the star of USNO �2.0 - 1050-6351075
(the star A in the figure in
http://grb.rssi.ru/GRB030329/030329_030329_at64.gif) is following:

Star A (USNO �2.0 - 1050-6351075)
RA =10 44 54.49
DEC=+21 34 29.8
R=14.00  B=14.90

JD Hel = 52728.2293  delR=0.17
                         .2318  delR=0.26
                         .2349   delR=0.23
                         .2397   delR=0.27

The figure of the OT can be found in
http://grb.rssi.ru/GRB030329/030329_030329_at64.gif

Preliminary results of photometry with  AZT-11 telescope of CrAO are
following:

start  (JD)  52728.26714
end   (JD)  52728.31593
Date  JD             U          B          V          R        I
52728.2932     14.25   14.95   14.49   14.02   13.65
52728.2932     0.018   0.019   0.030   0.017   0.027 error

CrAO telescopes will continue to monitor the OT.

This message may be cited.

J. Wren and W. T. Vestrand report on behalf of the RAPTOR team:

While the location of HETE-2 trigger 2652 was below our horizon at
the time of the GCN notice, we did obtain observations earlier in
the evening of the GRB field with one of our wide-field RAPTOR sky
monitors.  The observation nearest to the time of the burst was taken
at 05:58:39.56 UT, 5.64 hours before the event.  This image does not
show the optical counterpart to a 3-sigma limiting magnitude of
Rc=12.8.  Unfortunately, the weather degraded rapidly later in the
night, preventing further observations of this field.

A. Oksanen (Nyrola Observatory), R. Henriksson and M. Tuukkanen (the Finnish 
Deep Sky section of Astronomical Association Ursa) report:

We observed the optical afterglow of GRB030329 reported by Peterson and
Price (GCN 1985
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 ) visually about 8 hours after the burst. 

M. Tuukkanen observed the OT In Pornainen, Finland with a 0.63 m Newton
telescope for about one hour starting March 29, 2003 19:30 UT. 
He reported it as a faint starlike object seen easily with
direct vision. He did not see any flickering or distinct color.

R. Henriksson was observing in Orivesi, Finland with his 0.30 m Newton
telescope using 200x magnification at 20:05 UT. He reported the object 
stellar and faint, visible only with averted vision. His scanned sketch 
with notes is available on web:  

http://archive.ermiksson.net/record.php?id=4112

Both observers estimated the visual magnitude as 14.3 by using the 14.2
magnitude GSC 1434:322 star North of OT as reference.

This message may be cited.

GRB 030329: Optical pre-Imaging

C. Blake (Princeton) and J. S. Bloom (CfA) report:

"Using a signal-to-noise weighted stack of 50 NEAT images (taken from
1997-2002), we do not detect a counterpart at the position of the
transient afterglow of GRB 030329 (Price & Peterson; GCN #1985
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 ). The
images were acquired by R. Bambery, S. Pravdo, M. Hicks, and K. Lawrence
(Near-Earth Asteroid Tracking Project, Jet Propulsion Laboratory). We
therefore estimate the upper limit to the brightness of any host galaxy as
R=23.1 (2 sigma) or R=22.5 (3 sigma).  This result is consistent with the
somewhat more shallow limits reported in Wood-Vasey et al. (GCN #1998
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 ).
The absence of a host to such magnitude levels suggests a redshift of z >~
0.2, despite the extreme brightness of the early afterglow.

Within 7.5 arcseconds of the position of the OT, we find two sources
that are marginally detected (at the R=22.5 mag level):

------------------------------------------------------------------
      RA(J2000)       DEC                  Source-->OT
-------------------------------------------------------------------
 A: 10:44:49.776, +21:31:16.49    3.54" East, 1.66" North  d=3.91"
 B: 10:44:50.065  +21:31:10.77   -0.49" East, 7.38" North, d=7.40"

Positional errors relative to the USNO-B1.0 catalog are 0.5". These
sources are shown in an image linked from the webpage given below.
Photometric calibration of the stacked image was performed using the
USNO-B1.0 catalog. Some photometric secondary stars in the field are
listed below:

   RA(J2000)  DEC              R        B
		  	      mag      mag
-----------------------------------------------------
10:44:55.17 +21:28:11.3      17.69     18.48
10:44:43.40 +21:27:58.4      18.41     19.46
10:44:44.06 +21:27:18.5      18.52     20.47
10:44:53.61 +21:30:11.6      17.45     18.41
10:45:04.39 +21:29:56.1      18.22     20.37
10:44:55.67 +21:31:22.2      19.08     19.95
10:44:54.97 +21:31:42.7      18.51     20.36
10:44:48.68 +21:31:39.8      18.95     19.30
10:44:42.00 +21:32:31.7      15.08     18.18
10:44:50.44 +21:32:05.8      16.61     17.99
10:44:59.44 +21:31:43.9      18.07     19.84
-------------------------------------------------------

Finally, we note an object at (J2000) 10:44:55 +21:31:05.9, which
appeared in the DSS-II image, and is listed in the USNO-B1.0 as being
R=19.60, was detected at only R=21.9 in our stacked image."

A stacked image from NEAT that includes the WCS in the header may be
found at:
        http://astro.princeton.edu/~cblake/030329.html

This message can be cited.

P. Martini (OCIW), P. Berlind, K. Z. Stanek (CfA) and P. Garnavich
(Notre Dame):

We imaged the optical afterglow of GRB 030329 (Peterson & Price: GCN
1985
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 ; Torii: GCN 1986
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 ) with the Magellan 6.5-m Clay telescope and
LDSS2 imaging/spectrograph on March 30 UT 01:15 (13.6 hours after the
burst). We also obtained imaging data with the FLWO 1.2-m telescope.
The R-band magnitude is estimated to be 15.1 assuming star "A" is
R=16.2 (see

http://cfa-www.harvard.edu/~kstanek/grb030329.ps).

Thus the OT continues to be very bright. We should note that the
several fairly bright objects closest to the OT are clearly resolved
in our images and should not be used for relative photometry.  "A" and
"B" appear to be stellar at ~1.3'' seeing.

The foreground reddening from Schlegel et al. (1998) is E(B-V)=0.025.

This message may be cited.

P. Martini (OCIW), P. Garnavich (Notre Dame) and K.Z. Stanek (CfA)

Spectra of the optical afterglow of GRB 030329 (Peterson & Price,
GCN 1985
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 ; Torii: GCN 1986
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 ) were obtained with the
Magellan 6.5-m Clay telescope and LDSS2 imaging/spectrograph
starting at March 30.06 (UT). The spectra cover the wavelength
range of 4000 to 9000 Ang. with a resolution of 13 Ang. FWHM.
Preliminary analysis of the spectum of this bright GRB afterglow
shows a smooth blue continuum with no significant absorption
features. The only obvious feature is an unresolved emission
line at 5852 Ang. If this is [OII] emission from the host galaxy,
then the redshift is z=0.57. Further analysis is continuing.

This message may be cited.

[GCN OPS NOTE(02apr03): The date int he first line was corrected
from "GRB 030328" to "GRB 030329".]

E. Berger, A. M. Soderberg (Caltech) and D. A. Frail (NRAO) report on
behalf of a larger collaboration:

"We observed the position of the optical afterglow (GCN 1985
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 ) of GRB
030329 (GCN 1997
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 ) with the VLA on March 30.06 UT.  We detect a 3.5 mJy
source at 8.46 GHz coincident with the OT.  This is the brightest radio
afterglow detected to date, consistent with the unusual brightness of the
optical (e.g. GCNs 1986
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  & 1987) and X-ray (GCN 1996
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 ) counterparts, as well
as the prompt emission (GCN 1997
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 )"

This message may be cited.

R. Della Ceca, T. Maccacaro (INAF-OABrera), D. Fugazza, M. Pedani,
M. Cecconi (TNG), F. Fiore, L.A. Antonelli (INAF-OAR), S. Covino
(INAF-OABrera), E. Pian (INAF-OATs), N. Masetti (IASF-CNR) report:
 
"Starting on March 30 2003 00:43:40 UT we have obtained low resolution
(R~1000) spectra of the optical afterglow of GRB030329 (Peterson &
Price GCN #1985
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 , Torii, GCN #1986
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 ) using DOLORES at TNG.  Observations
consisted of two exposures of 15 min each the second obtained at 2.75hh 
after the first, and cover  the full spectral range 3800-8000 Angstrom, 
in relatively good seeing conditions (1.5").  At the time of the 
observations the afterglow magnitude was R~15-16 (e.g. Martini et al.
GCN #2012
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 ).
 
A preliminary analysis of the spectra reveals no strong absorption
features. A more detailed analysis is needed to search for faint
absorption lines.  A faint emission line at 5846 Angstrom (see Martini
et al. GCN# 2013) is present in the later spectra, when the afterglow
emission was less strong. If this is [OII] emission from the host
galaxy, then the redshift is z=0.568.

We detect a strong spectral variability between the first spectrum, 
when the afterglow was extremely blue, and the second spectrum, 
obtained starting from 03:25:35 UT.
 
We are particularly grateful to the TNG staff for their remarkable
support to these observations.

This message may be cited."

G. Masi (University of Rome " Tor Vergata" and ESO),
F. Mallia, U. Tagliaferri (Osservatorio Astronomico di Campo Catino, Italy),
B. L. Jensen and J. Hjorth (University of Copenhagen),
M. I. Andersen (Astrophysikalisches Institut Potsdam) report: 


We imaged the field around the OT located by Peterson & Price (GCN 1985
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 ) and 
Torii (GCN 1986
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 ), using the Campo Catino Automated Telescope (0.4-m f/8) + 
CCD (unfiltered, but peaking in the red part of the spectrum) on Mar 29.9621 
UT. The source was bright and our astrometry provided a position in 
excellent agreement with that in GCN 1994
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  (Uemura et al.). Using the R 
magnitudes for the USNO SA2.0 stars in the field, we obtained a preliminary 
magnitude of CR = 14.5. 

This message can be cited.

P.A. Price, B.P. Peterson and B.P. Schmidt (RSAA, ANU) report:

Synthesis of observations from Rykoff et al. (GCN #1995
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 ), Gal-Yam et
al. (GCN #1999
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 ), Martini et al. (GCN #2012
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 ) and from the SSO 40-inch
(GCN #1987
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 ) yeilds the following decay:

	R/mag ~ 15.8 + 2.4 log (t/days)

with corresponding power-law index alpha = 0.97 +/- 0.03.
Hence, though the afterglow is bright, the decay is not unusually
shallow (eg, 010222 had alpha1 ~ 0.80).

The spectral index, calculated from the B-I colour from Burenin et
al. (GCN #2001
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 ) and Rumyantsev et al. (GCN #2005
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 ) is beta ~ 1.2.

Using the measured redshift (Martini et al., GCN #2013
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 ; Della Ceca et al.,
GCN #2015
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 ), optical decay and spectral index, we calculate the R-band
absolute magnitude of the optical afterglow for t=1 day in the source
frame, M_R,1 = -26.7 mag.  This is therefore the most intrinsically bright
optical afterglow observed to date (with 000301C and 000418 tied for
second at M_R,1 = -26.1 mag).  The low redshift and the large intrinsic
brightness combined to produce an optical afterglow with a large apparent
brightness.

The redshift of z=0.57 and measured fluence (Vanderspek et al., GCN #1997
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 )
implies an isotropic-equivalent energy release of 1.1 x 10^53 erg (30-400
keV).  The Frail et al. "standard energy" result implies a jet-break time
of around 4 days.  At this time, the afterglow should be R ~ 17.3 mag.
We encourage polarimetric observations to be made on this timescale to
constrain the jet dynamics.

This message may be cited.

P. Garnavich (Notre Dame), K.Z. Stanek and P. Berlind (CfA) 

Photometry of the GRB 030329 afterglow (Peterson & Price: GCN
1985
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 ; Torii: GCN 1986
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 ) has been obtained with the Fred
L. Whipple 1.2m telescope beginning March 30.10 (UT). The
R-band images show a power-law decay index of -1.9 between
14 and 18 hours after the burst. This is significantly steeper
than the decay index of -0.9 derived from the photometry
of Rykoff & Smith (GCN 1995
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 ) and Burenin et al. (GCN 2001
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 )
obtained within 8 hours of the burst. A break in the light curve
appears to have occurred between 0.3 and 0.5 days after
the burst.

The post-break light curve is well fit by

               R=16.3+1.9*2.5*log(age in days)

with the calibration based on that of Martini et al. (GCN 2013
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 ).

This message may be cited.

D. A. Smith reports on behalf of the ROTSE collaboration:

The ROTSE-IIIb instrument at McDonald Observatory in Texas began observing the
optical counterpart to GRB 030329 as soon as it was possible to do so.  The
first calibrated image began at 30 March 02:27:31 (UTC).  Images were
calibrated against the R-band magnitudes of the USNO A2.0 catalog, and the
source was initially found to be at an unfiltered magnitude of 15.35+-0.06 and
fading.  Analysis of the first 70 images showed clearly that the rate of decay
had increased when compared to the observations recorded by ROTSE-IIIa the
night before (Rykoff & Smith, GCN Circ. 1995
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 ).  Separate power-law fits to each
instrument's data set indicated that the flux decay slope had shifted from
about 1.0 (consistent with the decay slope reported by Price, et al. GCN
Circ. 2017
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 ) to about 1.9 (consistent with the decay reported by Garnavich et
al. GCN Circ. 2018
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 ).  A plot of these decay curves along with the power-law
fits can be seen at http://www.rotse.net/transients/grb030329/).  An
extrapolation of these curves predicts a break time of about 12.1 h after the
burst.  

ROTSE-IIIb will continue to observe GRB 030329 as long as it is able to do so.

J. Greiner (MPE Garching), M. Peimbert (UNAM Mexico), C. Esteban (IAC Spain),
A. Kaufer, P. Vreeswijk, A. Jaunsen, J. Smoke (all ESO), S. Klose 
(Thueringer Landessternwarte) and O. Reimer  (Univ. Bochum) report
for a larger collaboration:

The optical afterglow (Peterson & Price, GCN 1985
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 ; Torii, GCN 1986
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 ) of 
the bright HETE (H2652) GRB 030329 was observed with the high-resolution
UVES spectrograph at the VLT unit Kueyen, starting around March 30.166 UT.
Quick-look analysis reveals several absorption and emission lines.
In particular, we find emission lines at 5680, 5850, and 7669 A
which we identify with Hbeta, [OIII]5007 and Halpha. Absorption lines
are clearly seen at 3270 A and 3334 A which we identify as the MgI 2853 and 
MgII 2800 doubletts. Based on these identifications we determine a redshift
of z=0.1685.  This is nearest GRB so far (except GRB 980425/SN1998bw), 
consistent with the exceptional brightness of this afterglow at all 
wavelengths.

We are highly indebted to the ESO staff at Paranal for their assistence, 
and K. Torii (RIKEN) for providing an early finding chart.

[GCN OPS NOTE(11jan13):  Per author's request, "Estaban" was changed
to "Esteban".]

J. P. Halpern, N. Mirabal, M. Bureau (Columbia U.), K. Fathi (U. Nottingham)
report for the MDM Observatory follow-up team:

We monitored the optical afterglow of GRB 030329 (=H2652, Vanderspek et al.
GCN 1997
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 ), identified by Peterson & Price (GCN 1985
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 ) and Torii (GCN 1986
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 ),
in the R-band with the MDM 1.3m for 7.5 hours beginning on March 30 03:05 UT, 
15.5 hours after the burst.  During this period, the magnitude declined from
R = 15.38 to R = 16.22, referenced to star "A" of Martini et al. (GCN 2012
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 ).
A fit to the 7.5 hour run yields a power-law decay slope of -1.934 +/- 0.005,
in agreement with contemporaneous measurements of Garnavich et al. (GCN 2018
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 ) 
and Smith (GCN 2019
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 ), although it is apparent that the slope is continuing to 
steepen further.

A graph of the preliminary differential magnitude light curve is available at

http://www.astro.columbia.edu/~jules/030329_lc.ps

We thank J. Kemp for providing the data reduction pipeline.

This message may be cited.

S. Zharikov (OAN SPM, IA UNAM, Mexico), E. Benitez, J. Torrealba, J.  
Stepanian (IA UNAM, Mexico) report: 

We have observed the GRB030329 OT
found by B.A. Peterson and P.A. Price (GCN 1985
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 ) with 1.5m and 2.1m
telescopes of SPM Observatory, BC, Mexico. A set of exposures in UBVRI
Bessel filters was obtained with 1.5m telescope under photometric
conditions. Standard stars RU 149 and PG 1633+099 from Landolt's catalogue
were used for photometric calibrations. The results of photometry are
following:
 30 March U B V R I
 UT 03:55 15.23 16.00 15.68 15.38 14.95
 UT 05:55 15.44 16.25 15.92 15.61 15.19
 UT 08:00 15.80 16.44 16.16 15.84 15.41
 UT 10:16 15.99 16.65 16.40 16.05 15.62 
Errors are about 0.02. 
USNO U1050_06350247 star with coordinates (AR=10 44 42; DEC=+21 32 32, 
J2000) can be used as the secondary standard in the OT field:
 B = 17.93(5); V =16.84(3); R = 16.04(2); I = 15.48(2)
 
The continuous light curve in the R band with exposures 240 and 120 sec 
was obtained during 6.5h from 03:55 UT utill 10:40 UT. We estimate the 
decline rate to be about 0.11 mag/hour.

Spectra of the optical afterglow of GRB 030329 were obtained with the
2.1-m telescope and B&Ch spectrograph (600l/mm) starting at 05:22 UT. The
spectra cover the wavelength range of 3900 to 6100 AA with a resolution of
2.2A/pix. Data analysis is in progress.

This message may be cited.

A. Henden (USRA/USNO) reports on behalf of the USNO GRB team:

We have acquired BVRcIc all-sky photometry for
a 11x11 arcmin field centered at the coordinates
of the optical transient (Peterson and Price, GCN 1985
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 )
for the HETE burst GRB030319 (GCN 1997
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 )
with the USNOFS 1.0-m telescope on one clear but very poor
seeing night.  Stars brighter than V=11.0 are saturated and
should be used with care.  We have placed the photometric data
on our anonymous ftp site:
ftp://ftp.nofs.navy.mil/pub/outgoing/aah/grb/grb030329.dat
The astrometry in this file is based on linear plate solutions
with respect to UCAC2.  The external errors are less than 100mas.
Due to the poor seeing, the external photometric error
is larger than normal for our calibrations.  This report
should be considered preliminary, with additional calibrations,
including U-band, to be performed later in the week when
weather conditions are better.

As always, you should check the dates on the .dat file prior to
final publication to get the latest photometry.

R. Burenin, R. Sunyaev, M. Pavlinsky, D. Denissenko, O. Terekhov,
A. Tkachenko (IKI); Z. Aslan, K. Uluc, I. Khamitov (TUG); U. Kiziloglu,
A. Alpar, A. Baykal (METU); I. Bikmaev, N. Sakhibullin, V. Suleymanov (KSU)

report:

The optical afterglow of GRB 030329 (Peterson and Price, GCN 1985
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 ) was
observed with 1.5-m Russian-Turkish Telescope RTT150 at Bakyrlytepe (TUBITAK
National Observatory, Turkey). The observations started at Mar 29.744 UT,
appr. 6 hours after the burst and lasted until Mar 30.061 UT, appr. 14 hours
after the burst.

During the night we have obtained approximately 200 images in each BVRI
Bessel filter with 10-30 s exposures. The photometric conditions were good.

To calibrate the OT flux from the beginning of our observations we were
using the star which later was named as "A" star by Martini et al. (GCN
2012
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 ). We assume this star is R=16.20 which agree well with our mean
photometric solution, obtained in previous nights. To calibrate OT flux in
other filters we assume the following magnitudes of this star: B=18.22,
V=17.02, I=15.42, measured using the same photometric solutions.

The optical transient showed no significant variations above the gradual
decline; the preliminary upper limit on short-term variability is 5%.

In the first 5 hours of our run we find that the R-band flux declines as
t**-1.1. During the last 2.5 hours we observed the smooth continuous change
in the slope of power law flux decay.

The fit of the post-break light curve reported by Garnavich et al. (GCN
2018
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 ) lies exactly on the continuation of our light curve. This suggests
that we are lucky to observe in detail the major change in the slope of the
light curve and measure its duration. The break occured in 12-14 hours after
the burst and lasted for appr. 2-4 hours.

The R magnitudes of the afterglow are:
       
t-t0,hours   R
 6.199	    14.10
 7.049	    14.26
 7.899	    14.38
 8.749	    14.52
 9.599	    14.64
10.449	    14.75
11.299	    14.84
12.149	    14.96
12.999	    15.06
13.849	    15.16

The preliminary light curve in R can be found at
http://hea.iki.rssi.ru/~br/lcl_030329_r.ps

The finding chart available at http://hea.iki.rssi.ru/~br/r_030329.gif

Further analysys of the lightcurve is underway. 

This message may be cited.

V.Rumyantsev, E.Pavlenko, O.Antoniuk (CrAO) and A.Pozanenko (IKI) report:

We continue to monitor the OT of GRB030329 (GCN  2025
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 ).

The OT found by Peterson and Price  (GCN 1985
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 ) is clearly visible in our
image taken
with Cassegrain 38-cm telescope of CrAO.Several 180 sec. exposures of  R
(Johnson) filter were obtained. Based on filed photometry by A. Henden (GCN
2023
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 )  we estimate the OT magnitude as

Mid Time (UT)          exposure      OT

March, 30 17:56:25     1x180 s      R = 16.61

The figure image can be found in http://grb.rssi.ru/GRB030329/

Detailed calibration and observations are continuing.

S. Klose, C. Hoegner (Thueringer Landessternwarte Tautenburg),
J. Greiner (MPE Garching)

report:


We observed the field of GRB 030329 (HETE trigger #2652) with the
Tautenburg Schmidt telescope equipped with the prime focus CCD camera
(2k x 2k). Based on the secondary standard star at RA, DEC (J2000) =
10:44:54.43, 21:34:28.6 (R=13.69, I=13.28) provided by Henden (GCN
2023
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 ), we measure for the afterglow R=16.4 at 18:54 -- 19:02 UT and
I=15.9 at 18:46 -- 18:54 UT with an estimated error of 0.1 mag.

C. Bartolini, A. Guarnieri, A. Piccioni (Bologna University), 
G. Gavazzi (Milano-Bicocca University), R. Gualandi (Bologna 
Astronomical Observatory), G. Pizzichini and P. Ferrero 
(IASF-CNR, Bologna) report:

By a preliminary reduction of four frames of our CCD UBVRI 
photometry of GRB030329 (GCN n.2003), performed with the 152 cm 
Loiano telescope, we obtain:


   mid exp.      filter     exposure time         mag  
     UT                       (seconds)    
   
Mar 29.7823        R            300           14.29 +/-.10
Mar 29.8556        R            180           14.55 +/-.03

Mar 29.7957        B            900           15.16 +/-.03
Mar 29.8493        B            300           15.38 +/-.03
 
Magnitude values were referred to star A (Martini et al, GCN 
2012
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 ) as calibrated by Burenin et al. (GCN 2024
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 ). The 
uncertainties have the meaning of internal errors. 



This message may be cited.

E. O. Ofek, A. Gal-Yam, Y. Lipkin, K. Sharon and E. Medezinski 
(Wise observatory, TAU) report:

We searched for archival CONCAM (www.concam.net) images 
covering the trigger time of GRB 030329 (March 29, 11:37:14, 
Ricker et al. GCN 1997
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 ). This part of the night was covered by 
CONCAM units at Kitt Peak and Mount Wilson Observatories. 
Unfortunately, CONCAM images for that night from Mauna Kea 
Observatory in Hawaii are uavailable on the net.

CONCAM images covering the exact time of the GRB
trigger do not appear in the web archives of both sites (Kitt
Peak and Mount Wilson). We were therefore limited to the analysis 
of images taken a few minutes before and after the GRB.
We could not detect an OT to a conservative limiting magnitude of 3.5.

The Kitt peak images are superior: four 180 s CONCAM images, 
taken at Mar 29, 11:29:57, 11:33:52, 11:41:46 and 11:45:42 UT
were searched. The magnitude limit is shallow as the GRB 
location was near the horizon at Keat Peak. 

If the instantaneous optical display associated with GRB 030329 
(z=0.1685, Greiner et al. GCN 2020
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 ) had been similar to that of GRB 990123 
(z=1.6), which peaked above mag 9, then after appropriate scaling 
by the luminosity distance (for a flat Universe with omega=0.3, 
neglecting effects of extinction), we would expect GRB 030329 
to be ~240 times brighter than GRB 990123. This means that an
optical source with mag ~3 should have been apparent on 
contemporaneous CONCAM images.

K. Lindsay, D. H. Hartmann (Clemson University), 
M. Leake, M. Williams (Valdosta State University)

Report on behalf of a larger collaboration:

We observed the optical afterglow of GRB 030329,
(=H2656, Vanderspek et al. GCN 1997
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 ), identified
by Peterson & Price (GCN 1985
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 ) and Torii (GCN 1986
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 ),
in the Johnson B-Band with the SARA 0.9m telescope at 
KPNO. We obtained 45, 300s exposures.  Observations
began at 02:55:09UT, and ended at 06:50:58UT, on March
30th.  The obsevations were carried out under good 
seeing conditions.  Aperture photometry was performed, 
and calibrated utilizing standards reported by Henden
et al., GCN 2023
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 .  During the observational period, 
the afterglow faded by approximately 0.5mag.  Further 
observations are planned. 

More information on the SARA Observatory
can be found at http://www.saraobservatory.org/.

This report may be cited.

Y. Lipkin, E. O. Ofek, A. Gal-Yam, Haim Mendelson (Wise observatory, TAU)
report:

We are observing the field of GRB 030329 (HETE trigger #2652, Ricker et al., GCN 1997
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 ) with the
TEK 1K CCD mounted on the 1-meter telescope of Wise Observatory, Israel.
Based on the secondary reference stars provided by Henden (GCN 2023
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 ,
RA, Dec (2000) = 10:44:39 +21:30:59, and 10:44:42 +21:32:32), we measure
a magnitude of R=16.40 for the OT at 17:20 UT

Preliminary analysis of 75 images, obtained during three hours of observations
(17.2 UT - 20.5 UT) yields a power-law decay rate (alpha) of 0.7 +/- 0.1.
It appears that the OT decline rate has flattened again, after the
reported break (Halpern et al. GCN 2021
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 ).

[GCN OPS NOTE (30Mar03): Haim Mendelson was added to the author list.]

V. Lipunov, A. Krylov, V. Kornilov, G. Borisov, D. Kuvshinov, A. Belinski,
I. Chilingarian, M. Kuznetsov, S. Potanin, V. Vitrischak, G. Antipov

Sternberg Astronomical Institute, Alexsandr Krylov Observatory, Moscow

report:

The OT of GRB030329 (Peterson and Price, GCN 1985
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 ) was observed with
MASTER system (280mm, http://observ.pereplet.ru, GCN 2002
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 ). We obtained
about 200 measurements in R filter, with calibration to several tens of
USNO A2.0 stars located in 15 arcmin field around the OT. Our
observations started at Mar 29, 17.1 UT (5.5 hours after the GRB) and had
been lasting for 8.5 hours up to Mar 30, 1.5 UT (13.9 hours after the GRB).

Corresponding to our observations, R-band flux declines as t^-1.0 (sligtly
differs from t^-1.1 reported by Burenin et al. GCN 2024
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 ). At the end of
observations the OT's brightness began to decrease more rapidly. We had
very poor transparancy at that time, so flux measurements uncertanities
were quite big, therefore we can't confirm or refute -1.9 index reported
by Garnavich et al. (GCN 2018
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 ).

Our lightcurve based on 114 measurements available at:
http://observ.pereplet.ru/images/GRB030329_R_lc.gif
http://www.sai.msu.su/~chil/GRB030329_R_lc.ps

Further analysis of the obtained data is underway.

This message may be cited.

D. Q. Lamb, D. York, J. Barentine, B. Ketzeback, J. Dembicky,
R. McMillan,  M. Nysewander and D. Reichart report on behalf of the ARC
and UNC GRB teams of the FUN GRB collaboration:

J-, H-, and K-band photometry of the optical afterglow (Peterson and
Price, GCN 1985
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 ) of GRB030329 (Vanderspek et al., GCN 1997
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 ) were
obtained using the ARC 3.5-m telescope and the GRIM II at APO, starting
at 4.712 UT and ending at 5.651 UT on March 30.  The measured J-band
magnitudes of the afterglow are given below:

                         ------------------------
                          UT            J
                         ------------------------
                         4.712   14.230 +/- 0.047
                         4.961   14.307 +/- 0.077
                         5.425   14.596 +/- 0.119
                         5.570   14.501 +/- 0.075
                         ------------------------


Assuming a model F(nu) ~ F_0 (nu/nu_0)^alpha, the spectral slope of the
flux from the J-band through the K-band at the time of the first cycle
of observations is alpha = - 0.8 +/- 0.1.

K.Z. Stanek (CfA), P. Martini (OCIW) and P. Garnavich (Notre Dame) 

Images of the GRB 030329 afterglow (Peterson & Price: GCN
1985
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 ; Torii: GCN 1986
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 ) were obtained with the Magellan 6.5-m
Clay telescope beginning March 31.068 (UT). Four 30-sec exposures
were taken in the R-band with the LDSS2 imaging/spectrograph.
Using the calibration by Henden (GCN 2023
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 ) for "star A" (GCN 2012
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 )
at 10:44:42 +21:32:31 (2000) of R=16.06, we find the brightness
of the afterglow is R=16.21 +/- 0.05.

This is nearly a magnitude brighter than expected from the
extrapolation of a powerlaw decay slope of -1.9 found around
16 hours after the burst by Garnavich, Stanek & Berlind (GCN 2018
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 ),
Smith (GCN 2019
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 ) and Halpern et al. (GCN 2021
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 ). Apparently, a
more shallow decay has reappeared as reported by Lipkin et al.
(GCN 2034
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 ).

We combined the Clay images, taken in 1" seeing, and subtracted
the afterglow point-spread function but no evidence of the
host galaxy was detected.

This message may be cited.

J. Schaefer, S. Savage (University of Wyoming)

Report on behalf of the University of Wyoming GRB response team and the
FUN GRB collaboration:

We observed the optical afterglow of GRB 030329,  identified in (GCN
1986
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 ), in the Johnson V-Band with the RBO 0.6m telescope at Red Buttes
Wyoming.  We obtained 6, 180s exposures on March 30th UT. The observations
were carried out under fair to poor conditions.  Aperture photometry was
performed and calibrated utilizing the standards reported by Henden et
al., (GCN 2023
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 ).
We initially measured the magnitude of the OT to be V=15.57 +/- 0.01 at
02:59UT which faded by 0.06 during the short observational period.




Further observations are currently being undertaken, and more data for the
V filter will follow.

This message may be cited

GRB 030329 (= H2652) (GCN 1985
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  and many others) was observed with the 
Ryle Telescope at Cambridge, UK from 2003 Mar 30 16:35 UT to 
2003 Mar 31 03:30 UT. The mean flux density at 15.2 GHz was 9.8 mJy
(cf 3.5 mJy at 8,46 GHz approximately 24h earlier - GCN 2014
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 ).
Over the period of the observation the flux density increased from 
7 to 12 mJy. A light curve may be seen at 
http://www.mrao.cam.ac.uk/~guy/grb/GRB030329-030330.ps

T. Murakami, D.Yonetoku, H.Izawa, T.Uchida, N.Hirosawa and M.Suzuki
report:

 We observed the afterglow of GRB 030329 (HETE trigger #2652) at
Kanazawa, Japan, discovered by Peterson & Price (GCN 1985
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 ) and Torii
(GCN 1986
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 ). We have started observations at 13:33:34 UT. (2 hours
after the burst ) until 18:55 UT, 30-s integration was repeated. The
object was 13.1+/-0.1 mag preliminary (refer to USNO-A2.0 red) at
the first frame with 25cm/f4.8 telescope equipped with unfiltered
CCD(KAF0261E).

Y. Lipkin, E. O. Ofek, A. Gal-Yam, E. M. Leibowitz, H. Mendelson (Wise observatory, TAU)
report:

Observations of GRB 030329 (HETE trigger #2652, Ricker et al., GCN 1997
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 )
with the TEK 1K CCD mounted on the 1-meter telescope of Wise Observatory, Israel
revealed that starting approximately March 30 21:00 UT, the OT brightened.

The light curve, decaying with a power-law index alpha=0.7 (Lipkin et al. GCN 2034
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 ),
reached a minimum R-band magnitude of about 16.45 at approximately 21:00 UT.
Over the next three hours the OT brightened, reaching R=16.25 at approximately
March 31.0 UT, consistent with later observations by Stanek et al. (GCN 2041
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 ).

R. Burenin, R. Sunyaev, M. Pavlinsky, D. Denissenko, O. Terekhov,
A. Tkachenko (IKI); Z. Aslan, K. Uluc, I. Khamitov (TUG); U. Kiziloglu,
A. Alpar, A. Baykal (METU); I. Bikmaev, N. Sakhibullin, V. Suleymanov (KSU)

report:

The optical afterglow of GRB 030329 (Peterson and Price, GCN 1985
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 ) was
observed with 1.5-m Russian-Turkish Telescope RTT150 at Bakyrlytepe (TUBITAK
National Observatory, Turkey; see also GCN 2001
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  and 2024
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 ) in the night of
March 30/31. The R magnitudes of the afterglow are:

t-t0,hours       UT       R

34.69          30.961    16.5
38.12          31.073    16.39

The magnitude of "A" star was assumed to be R=16.20. First observation was
made under poor sky conditions in R filter only. Second set of four images
was obtained in each of BVRI filters.

This message may be cited.

A. Zeh, S. Klose (Thueringer Landessternwarte Tautenburg),
M. Nysewander, D. Reichart (University of North Carolina at Chapel Hill),
J. Greiner (MPE Garching)

report:

We selected from the GCN literature all available R-band data of the
afterglow of GRB 030329 (including the unfiltered ROTSE data; Rykoff
and Smith, GCN 1995
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 ). We fitted the afterglow light curve using the
standard Beuermann equation (A&A 352, L26). The result is: alpha_1 =
0.85 +/- 0.07, alpha_2 = 1.45 +/- 0.09, t_break = 0.39 +/- 0.06
days. The substantial re-brightening reported by Lipkin et al.  (GCN
2045
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 ) and Burenin et al. (GCN 2046
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 ) seems to be similar to that seen
in the afterglow light curve of GRBs 000301C and 021004. A plot including
a predicted supernova component and assuming a negligible contribution
from an underlying host galaxy is available via anonymous ftp from
ftp.tls-tautenburg.de, dir /pub/klose/10/. A multi-color plot is
available at http://www.physics.unc.edu/~mnysewan/grb030329.html.

A. Zeh, S. Klose, U. Laux (Thueringer Landessternwarte Tautenburg),
J. Greiner (MPE Garching)

report:


Recent observations with the Tautenburg Schmidt telescope indicate that
the afterglow of GRB 030329 has stopped re-brightening. We measure
R=16.8 +/- 0.1 on images taken at 18:43 UT. Multi-color observations
are ongoing.

Y. Lipkin,  E. M. Leibowitz, E. O. Ofek, A. Gal-Yam, H. Mendelson 
(Wise observatory, TAU) report:

We are conducting time-resolved photometry of GRB 030329 (HETE 
trigger #2652, Ricker et al., GCN 1997
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 ) with the TEK 1K CCD mounted 
on the 1-meter telescope of Wise Observatory, Israel.

During 3 hours of observations, starting at March 31 17:00 UT, the OT is 
constant (to within 0.1 mag), with a mean magnitude of approximately 
R=16.8, consistent with the findings of Zeh et al (GCN 2048
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 ).

E.Pavlenko, V.Rumyantsev, O.Antoniuk, N.Primak  (CrAO) and A.Pozanenko (IKI)
report:

We continue to monitor the OT of GRB030329 (GCN  2005
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 , 2028
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 ).

The OT found by Peterson and Price  (GCN 1985
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 )  was imaged Cassegrain 38-cm
telescope of CrAO.  Several 240 sec. exposures in  R (Johnson) spectral band
were obtained. Based on filed photometry by A. Henden (GCN 2023
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 )  we
estimate the OT magnitude as

Mid Time (UT)                  exposure             OT
March, 31 17:50:40            240 sec         16.92 +/-0.04

Taking into account R=16.8 +/- 0.1 at  18:43  obtained by A. Zeh, et al.
(GCN 2048
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 ) one may suggest that light curve of OT starts new episode of
re-brightening or flattering is still continuing.

Detailed calibration and observations are continuing.

R. Burenin, R. Sunyaev, M. Pavlinsky, D. Denissenko, O. Terekhov,
A. Tkachenko (IKI); Z. Aslan, K. Uluc, I. Khamitov (TUG); U. Kiziloglu,
A. Alpar, A. Baykal (METU); I. Bikmaev, N. Sakhibullin, V. Suleymanov (KSU)

report:

We observed the GRB 030329 afterglow (Peterson and Price, GCN 1985
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 ) with
1.5-m Russian-Turkish Telescope RTT150 at Bakyrlytepe (TUBITAK National
Observatory, Turkey). The observations started at Mar 31.724 UT.

OT magnitude in all BVRI Bessel filters was constant during first 1.5 hours
of our observation. We measured R=16.91 for the OT, assuming that magnitude
of "A" star is R=16.20.

This message may be cited.

F.E. Marshall (NASA/GSFC), C. Markwardt (U.Md. & NASA/GSFC),
and J.H. Swank (NASA/GSFC) report:

RXTE re-observed GRB 030329 for a total of 3.9 ks
starting at March 30.724 UT (about 1.240 days after the burst).
The flux was about 0.9e-11 ergs/s/cm**2 in the 2-10 keV band
or about 15 times weaker than during the RXTE
observation the previous day (Marshall and Swank, GCN 1996
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 ).
The total light curve is well described by a simple model
in which the flux decays as t^(-1.5).
More complicated models are also consistent with the 
sparsely sampled data. For example, 
a model in which the decay rate increases 
from  t^(-1.1) at early times (Burenin et al., GCN 2024
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 ) to
t^(-1.934) at late times (Garnavich et al., GCN 2018
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 ;
Smith, GCN 2019
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 ; Halpern et al., GCN 2021
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 )
fits the data if the break occurs 0.54 days after the burst.

N. Caldwell (CfA), P. Garnavich, S. Holland (Notre Dame),
  T. Matheson and K.Z. Stanek (CfA)

Spectra of the optical afterglow of GRB 030329 (Peterson & Price,
GCN 1985
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 ; Torii: GCN 1986
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 ) were obtained with the
6.5-m MMT and Blue-Channel spectrograph on March 30 and 31 (UT)
The low-resolution spectra cover the wavelength
range of 3500 to 8500 Ang. with a resolution of 7 Ang. FWHM.
Analysis of the spectrum taken in good seeing on March 31
shows several narrow emission lines. The line seen at
5852 Ang. by Martini et al. (GCN 2013
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 ) and Della Ceca et al.
(GCN 2015
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 ) is, in fact, [OIII] 5007 and confirms the redshift
estimate of Greiner et al. (GCN 2020
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 ) of z=0.168.

In a 1.25" wide slit we find the following observed fluxes:

 observed      ID        z     Flux (10^-16 erg/cm^2/s)
  7669.2  Halpha 6563  0.1686       4.5
  5851.1  [OIII] 5007  0.1686       4.1  
  5795.4  [OIII] 4959  0.1687       1.6
  5681.7  Hbeta  4861  0.1687       1.5
  4356.1  [OII]  3727  0.1687       1.2

A narrow absorption line is detected at 3933.2 Ang. 
with an equivalent width of 0.4 Ang. and is probably
due to CaII in our Galaxy.

An estimate of the star formation rate in the 4 kpc
of the host galaxy nearest the burst can be made
from the [OII] luminosity (Kennicutt 1998, ARAA, 36, 189;
assuming H0=72).  The rate is an anemic ~0.1 Solar masses/yr.
without correcting for host extinction. The Halpha/Hbeta
ratio is not well determined from these data, but does not
imply a large extinction. We therefore conclude that the
SFR of the GRB 030329 host is very low.


This message may be cited.

[GCN OPS NOTE(02apr03): The SFR was corrected from "... an anemic ~0.01 ..."
to "... an anemic ~0.1 ...".]

R. Burenin, R. Sunyaev, D. Denissenko, M. Pavlinsky,  O. Terekhov,
A. Tkachenko (IKI); Z. Aslan, K. Uluc, I. Khamitov (TUG); U. Kiziloglu,
A. Alpar, A. Baykal (METU); I. Bikmaev, N. Sakhibullin, V. Suleymanov (KSU)

report:

We continue observations of the GRB 030329 optical afterglow (Peterson
and Price, GCN 1985
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 ) with 1.5-m Russian-Turkish Telescope RTT150
at Bakyrlytepe. Assuming that star "A" has R=16.20 we have measured
the following magnitudes:

t-t0,hours       UT       R

54.3     March 31.75     16.91
55.2           31.78     16.92
57.1           31.86     16.99

We see the beginning of new phase of fading of the optical afterglow.

This message may be cited.

J. Brodney Fitzgerald and Jerome A. Orosz (San Diego 
State University) report:

We have observed the field of GRB 030329 (Peterson & Price, GCN 1985
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 )
with the 1 meter telescope at the Mount Laguna Observatory (located 45
miles east of downtown San Diego at a dark site in the Cleveland
National Forest at an altitude of 6100 feet or 1859 meters) on the
nights of 2003 March 30 and 31 (UT).  We used a Loral 2048 x 2048 CCD
(binned 2 x 2) and Bessell B, V, R, and I filters.  Both nights were
photometric.  The instrumental time series were obtained using
Stetson's programs DAOPHOT, ALLSTAR, and DAOMASTER.  The instrumental
magnitudes were placed on the standard scales using Hendon's (GCN
2023
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 ) calibration.  Our observations are summarized in the 4 tables
below.  The errors quote include only the DAOPHOT errors, and do not
include errors in the zero points (estimated to be a few percent).
The CCD images of the GRB field and some Landolt fields are available
upon request to orosz@sciences.sdsu.edu.  Further observations are
planned for the night of April 1 (UT).

We also report the discovery of a possible eclipsing binary in the
field.  The J2000 coordinates are 10:44:36.81, +21:26:58.8 (taken from
Hendon's list given in GCN 2023
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 ).  The star was at a minimum
brightness around March 31 at 4:30 UT.  Over the next three hours it
brightened by about 0.6 magnitudes in all the filters.  The brightness
level was roughly constant between about 8:10 UT and 11:00 UT.  The
star was apparently constant on the night of March 30, although this
conclusion is somewhat weak owing to the fact that it was saturated in
many of our images.  The following table gives the extreme magnitudes
observed:

Filter    Min Mag    Max Mag
-----------------------------
  B        14.36      13.77
  V        14.00      13.41
  R        13.78      13.11
  I        13.60      13.00

Our GRB observations follow: 

Table 1:  B Observations:

  date-obs at start     exptime     mag      err
                         (sec)                  
-------------------------------------------------
2003-03-30T04:39:56.10  600.000    16.263   0.008
2003-03-30T05:19:08.50  480.000    16.321   0.010
2003-03-30T06:21:03.50  480.000    16.415   0.006
2003-03-30T07:24:03.20  480.000    16.510   0.004
2003-03-30T08:01:23.30  480.000    16.577   0.004
2003-03-30T08:50:07.70  480.000    16.648   0.004
2003-03-30T09:38:09.20  480.000    16.712   0.005
2003-03-30T10:38:02.00  480.000    16.889   0.013
2003-03-31T03:49:47.10  240.000    17.060   0.008
2003-03-31T04:09:46.30  240.000    17.087   0.009
2003-03-31T04:53:02.80  300.000    17.112   0.008
2003-03-31T05:16:57.30  300.000    17.140   0.008
2003-03-31T05:39:42.70  300.000    17.172   0.008
2003-03-31T06:17:01.30  300.000    17.191   0.008
2003-03-31T06:41:33.10  300.000    17.239   0.006
2003-03-31T07:17:46.30  300.000    17.246   0.009
2003-03-31T07:40:25.90  300.000    17.243   0.007
2003-03-31T08:03:53.90  300.000    17.285   0.009
2003-03-31T08:09:22.40  300.000    17.293   0.008
2003-03-31T08:48:31.90  300.000    17.296   0.007
2003-03-31T09:10:50.10  300.000    17.309   0.007
2003-03-31T09:33:07.30  300.000    17.327   0.007
2003-03-31T09:55:57.70  300.000    17.361   0.010
2003-03-31T10:42:17.30  300.000    17.374   0.012
2003-03-31T11:05:04.70  300.000    17.385   0.014


Table 2:  V Observations:

  date-obs at start      exptime     mag     err
                          (sec)                  
-------------------------------------------------
2003-03-30T04:39:56.10   600.000   15.8732  0.011
2003-03-30T05:19:08.50   480.000   15.9492  0.007
2003-03-30T06:21:03.50   480.000   16.0532  0.007
2003-03-30T07:24:03.20   480.000   16.1452  0.004
2003-03-30T08:01:23.30   480.000   16.1642  0.041
2003-03-30T08:50:07.70   480.000   16.2722  0.004
2003-03-30T09:38:09.20   480.000   16.3632  0.005
2003-03-30T10:38:02.00   480.000   16.4142  0.007
2003-03-31T03:54:27.10   240.000   16.6532  0.006
2003-03-31T04:15:22.50   240.000   16.6672  0.011
2003-03-31T04:59:11.40   300.000   16.7222  0.006
2003-03-31T05:22:35.30   300.000   16.7522  0.007
2003-03-31T05:45:20.50   300.000   16.7572  0.008
2003-03-31T06:23:02.00   300.000   16.7942  0.006
2003-03-31T06:47:19.40   300.000   16.8242  0.007
2003-03-31T07:23:20.20   300.000   16.8622  0.006
2003-03-31T07:46:01.50   300.000   16.8722  0.006
2003-03-31T08:14:56.30   300.000   16.8802  0.007
2003-03-31T08:20:24.00   300.000   16.8702  0.007
2003-03-31T08:54:07.40   300.000   16.9002  0.006
2003-03-31T09:16:24.00   300.000   16.9002  0.007
2003-03-31T09:38:42.50   300.000   16.9172  0.007
2003-03-31T10:01:27.30   300.000   16.9292  0.008
2003-03-31T10:06:57.80   300.000   16.4682  0.010
2003-03-31T10:12:26.00   300.000   16.9592  0.009
2003-03-31T10:48:07.50   300.000   16.9402  0.012
2003-03-31T11:10:40.10   300.000   16.9662  0.014


Table 3:  R Observations:

  date-obs at start      exptime    mag    err
                          (sec)                  
-------------------------------------------------
2003-03-30T04:39:56.10   600.000  15.402  0.006
2003-03-30T05:19:08.50   480.000  15.524  0.007
2003-03-30T06:21:03.50   480.000  15.694  0.009
2003-03-30T07:24:03.20   480.000  15.801  0.004
2003-03-30T08:01:23.30   480.000  15.841  0.005
2003-03-30T08:50:07.70   480.000  15.917  0.004
2003-03-30T09:38:09.20   480.000  16.004  0.006
2003-03-30T10:38:02.00   480.000  16.048  0.006
2003-03-31T03:59:42.40   240.000  16.277  0.009
2003-03-31T04:20:13.10   240.000  16.313  0.024
2003-03-31T05:04:46.90   300.000  16.356  0.006
2003-03-31T05:28:31.20   300.000  16.378  0.005
2003-03-31T05:50:50.80   300.000  16.392  0.007
2003-03-31T06:29:05.50   300.000  16.421  0.006
2003-03-31T06:52:51.60   300.000  16.459  0.005
2003-03-31T07:28:53.20   300.000  16.479  0.006
2003-03-31T07:51:53.40   300.000  16.487  0.007
2003-03-31T08:26:10.70   300.000  16.516  0.022
2003-03-31T08:31:42.00   300.000  16.509  0.006
2003-03-31T08:59:40.10   300.000  16.536  0.007
2003-03-31T09:21:55.50   300.000  16.535  0.006
2003-03-31T09:44:13.50   300.000  16.539  0.008
2003-03-31T10:18:09.40   300.000  16.560  0.007
2003-03-31T10:29:22.00   300.000  16.555  0.009
2003-03-31T10:53:41.70   300.000  16.577  0.007
2003-03-31T11:16:11.50   300.000  16.583  0.015


Table 4:  I Observations:

  date-obs at start      exptime    mag      err
                          (sec)                  
-------------------------------------------------
2003-03-30T04:39:56.10   600.000  15.0006   0.009
2003-03-30T05:19:08.50   480.000  15.1076   0.012
2003-03-30T06:21:03.50   480.000  15.2816   0.007
2003-03-30T07:24:03.20   480.000  15.3916   0.004
2003-03-30T08:01:23.30   480.000  15.4266   0.027
2003-03-30T08:50:07.70   480.000  15.5186   0.005
2003-03-30T09:38:09.20   480.000  15.6376   0.008
2003-03-30T10:38:02.00   480.000  15.7036   0.011
2003-03-31T04:04:32.10   240.000  15.8716   0.008
2003-03-31T04:25:02.80   240.000  15.8926   0.010
2003-03-31T05:10:34.50   300.000  15.9396   0.006
2003-03-31T05:34:03.50   300.000  15.9596   0.006
2003-03-31T05:56:25.90   300.000  15.9946   0.006
2003-03-31T06:35:53.60   300.000  16.0276   0.007
2003-03-31T06:58:26.10   300.000  16.0536   0.006
2003-03-31T07:34:51.90   300.000  16.0826   0.008
2003-03-31T07:58:11.70   300.000  16.0746   0.008
2003-03-31T08:37:12.10   300.000  16.0836   0.008
2003-03-31T08:42:40.70   300.000  16.1066   0.006
2003-03-31T09:05:09.40   300.000  16.1026   0.007
2003-03-31T09:27:28.10   300.000  16.1196   0.008
2003-03-31T09:49:53.50   300.000  16.1346   0.009
2003-03-31T10:23:41.20   300.000  16.1386   0.009
2003-03-31T10:35:00.70   300.000  16.1716   0.013
2003-03-31T10:59:14.40   300.000  16.1476   0.012
2003-03-31T11:21:45.60   300.000  16.1626   0.019

References:

Hendon, A., et al. 2003, GCN 2023
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Landolt, A. U. 1992, AJ, 104, 340
Peterson, B, A. & Price, P. 2003, GCN 1985
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Stetson, P. B. 1987, PASP, 99, 191
 


-------------------------------------------------------------------------
                             Jerome A. Orosz
      Assistant Professor of Astronomy, San Diego State University
             5500 Campanile Drive, San Diego, CA 92182-1221
(619) 594-7118 (office), 594-6182 (dept. secretary), 594-1413 (dept. fax) 
               http://mintaka.sdsu.edu/faculty/orosz/web/

A. Price (AAVSO) reports on behalf of the AAVSO International GRB Network:

The AAVSO International GRB Network has obtained B, V, R, and unfiltered
photometry of the afterglow to GRB030329 from numerous sources across the
globe over the past 3 days. See notes for details and access to time
series data.

Berto Monard, South Africa
  Unfiltered = 14.06 @ 2003.03.29 17:15 to
  Unfiltered = 15.01 @ 2003.03.29 23:37
  exposures: 317X45-60s 

Arto Oksanen, 0.4m at Nyrola Observatory, Finland
  R = 14.50 @ 2003.03.29 20:22:23 to
  R = 14.75 @ 2003.03.29 22:28:03
  exposures: 10X120s (out of 148 total)

Tim Schrabback and Anja von der Linden, 1.06m at Observatory
Hoher List of Bonn University, Germany
  R = 15.0 @ 2003.03.29 22:55
  exposure: 1800s

Peter Brown, 0.41m at Orson Pratt Observatory, Brigham Young
University, Utah USA
  R = 15.2 @ 2003.03.30 02:38 to
  R = 16.2 @ 2003.03.30 10:41
  exposures: 1X300s 

Dan Kaiser, 0.35m at Crescent Moon Observatory, Indiana USA
  V = 16.62 2003.03.31 01:32:04 to
  V = 16.97 2003.03.31 06:18:06
  R = 16.26 2003.03.31 02:10:12 to
  R = 16.53 2003.03.31 06:22:37

Bill Aquino, 0.3m with Buffalo Astronomical Association in 
New York, USA
  V = 16.71 @ 2003.03.31 05:33:03
  exposures: 4X180s exposure 

Notes:
 * Detailed reports (observing equipment, location, conditions, etc.)  
and many original FITS files available at
ftp://ftp.aavso.org/grb/GRB030329 or by e-mailing aavso@aavso.org.
 * Brown, Kaiser, Monard, and Oksanen have time series data spanning the
observations posted here. Full data has already been or will be posted
soon to the URL above.
 * Aquino, Kaiser, and Oksanen used comparison star photometry from Henden
et al. (GCN 2023
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 ). Brown used comp star A described on the finder chart by
Rumyantsev et al. (GCN 2005
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 ). Schrabback et al. used comp star A described
on a different finder chart by Martini et al.(GCN 2012
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 ). Monard's comp
star is from USNOA2, 14.0R, 3' NNE of GRB.
  * The decay rate in Monard's exposure varies from 0.191 CR/h in the
beginning of the run to 0.103 CR/h at the end. Kaiser's time series data
is fairly constant until about 5:40 when the OT begins to fade again.

  The CCD used by Oksanen plus other components of the AAVSO International
GRB network were funded by a generous grant from the Curry Foundation.

K. Lindsay, D. H. Hartmann (Clemson University), 
M. Leake, M. Williams (Valdosta State University)

Report on behalf of a larger collaboration:

We observed the optical afterglow of GRB 030329,
(=H2656, Vanderspek et al. GCN 1997
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 ), identified
by Peterson & Price (GCN 1985
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 ) and Torii (GCN 1986
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 ),
in the Johnson B-Band with the SARA 0.9m telescope at 
KPNO. We obtained 30, 300s exposures.  Observations
began at 02:58:24UT, and ended at 05:31:22UT, on March
31st.  The obsevations were carried out under good 
seeing conditions.  Aperture photometry is being 
carried out, and further observations are planned. 

More information on the SARA Observatory
can be found at http://www.saraobservatory.org/.

This report may be cited.

Y. Lipkin,  E. M. Leibowitz, E. O. Ofek, S. Kaspi, A. Gal-Yam,
H. Mendelson (Wise observatory, TAU) report:

We continue our time-resolved photometry of GRB 030329. Following a brief
standstill (Lipkin et al, GCN 2054
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 ), the OT decayed in brightness from
March 31 20:00 to March 31 23:15, reaching a minimum of approximately
R=16.9. At that time the trend reversed direction again and from 23:15 to
01:30 UT we detected a rebrightening of the OT by approximately 0.1
magnitude.

S. Savage, J. Schaefer, D. Gibbs (University of Wyoming)

Report on behalf of the University of Wyoming GRB response team and the
FUN GRB collaboration:

We observed the optical afterglow of GRB 030329, identified in Torii (GCN
1986
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 ), in the Johnson V filter with the RBO 0.6m telescope at Red Buttes
Wyoming.  We obtained 25, 300s exposures.  Observations were undertaken
between 02:26UT and 6:00UT, on March 31st.  The observations were carried
out under fair seeing conditions.  Aperture photometry was performed and
calibrated utilizing the standards reported by Henden et al., (GCN 2023
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 ).
We initially measured the magnitude of the OT to be V=16.71, which faded
by 0.15 mag during our observational period; however, there appeared to be
a brightening.  Errors were on average +/- 0.018.  

Further aperture photometry is being performed and observations are
planned.


This message may be cited.

Subject: GRB 030329: KAIT optical photometry

Weidong Li, Ryan Chornock, Saurabh Jha, and Alexei V. Filippenko (UC Berkeley)
report:

We have observed the GRB 030329 afterglow (Peterson & Price, GCN 1985
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 ) with 
the Katzman Automatic Imaging Telescope (KAIT) on the nights of 2003 Mar 30 
and 31 UT. 16 sets of UBVRI images were taken. Aperture photometry was
performed on the afterglow and some local standard stars in IRAF, and the 
instrumental magnitudes were transformed to the standard BVRI system using
the calibration provided by Henden (GCN 2023
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 ). We have also applied color
corrections to the KAIT data based on well-measured color terms for the KAIT
filters. Due to the lack of U-band calibrations, only BVRI images were reduced.
Our R-band photometry is summarized in the table below.  The errors quoted
include both the IRAF aperture photometry error and the magnitude
transformation error.


Table: KAIT R-band observations

t-t0 (hours) exptime   mag   err

 16.5662  300.0  R  15.424  0.034
 17.0989  150.0  R  15.448  0.032
 17.4775  150.0  R  15.487  0.022
 18.4173  150.0  R  15.618  0.028
 18.7934  150.0  R  15.659  0.023
 19.6814  300.0  R  15.724  0.023
 20.1812  150.0  R  15.809  0.057
 20.6912  150.0  R  15.825  0.016
 21.0689  150.0  R  15.899  0.030
 21.4514  150.0  R  15.907  0.035
 21.8964  150.0  R  15.948  0.035
 22.2831  150.0  R  15.965  0.037
 22.6695  150.0  R  16.102  0.079
 43.1320  300.0  R  16.560  0.031
 44.6242  300.0  R  16.763  0.136   (observed under cloudy conditions)
 45.9700  300.0  R  16.600  0.135   (observed under cloudy conditions)

This message may be cited.

Weidong Li, Ryan Chornock, Saurabh Jha, and Alexei V. Filippenko (UC Berkeley)
report:

We selected from the GCN literature all available R-band measurements of
the GRB 030329 afterglow. We fitted a smoothly broken power-law model
(Beuermann et al. 1999, A&A 352, L26; Stanek et al. 2001, ApJ 563, 592)
to the data within 24 hours of the burst, and obtained the following
parameters: alpha_1 = -0.75 +/- 0.06, alpha_2 = -1.90 +/- 0.05, t_break
= 0.44 +/- 0.04 days, and s = 5 +/- 2. Our fitting parameters are similar
to those reported by Zeh et al. (GCN 2047
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 ) except for alpha_2 (ours is much 
steeper). A plot showing the fit can be found at

http://astron.berkeley.edu/~bait/grb/grb030329.fit.ps

while a table of GCN R-band photometry of GRB 030329 can be found at

http://astron.berkeley.edu/~bait/grb/gcn030329.r.dat

which includes citations for all the data points used in the plot.

The substantial re-brightening reported by Lipkin et al. (GCN 2045
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 ) and
Burenin et al (GCN 2046
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 ) is apparent in the plot. Applying the above fitting
parameters to epochs after t = 24 hours, we found that the residual component
brightened steeply starting from t = 22 hours and reached a peak of 16.8 mag
at t = 40 hours, then declined gradually thereafter. Attempts to fit this
component with the R-band light curve of the hypernova SN 1998bw all failed;
thus the re-brightening may not be caused by a SN component.

Analysis of the color of the GRB from KAIT photometry during this phase
suggests the afterglow has a roughly constant color of (B-V) = 0.26 +/-
0.02 mag, (V-R) = 0.36 +/- 0.02 mag, and (V-I) = 0.78 +/- 0.02. (The data
of Fitzgerald & Orosz, GCN 2056
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 , suggests a constant (B-V) = 0.39 +/- 0.02
mag; there is an offset from the KAIT B photometry, perhaps due to a color
term). The constant color during the phase of the re-brightening is additional
evidence against a SN component explanation, in which significant color
changes are expected when the SN rises to the maximum.

Density inhomogeneities and extra energy sources are possible explanations 
for the re-brightening. 

This message may be cited.

J. Brodney Fitzgerald and Jerome A. Orosz (San Diego State University)
report:

We have a correction to GCN 2056
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  to report. Our tables of observations
contained errors in the observation times for our March 30 data.  The
start times for the B filter were also listed in the tables for the V, R,
and I filters.  We give below the correct tables for the March 30
observations.  The times for the March 31 observations are correct.
We regret any inconvenience this error may have caused and
thank Weidong Li for bringing this error to our attention.

B data:

2003-03-30T04:39:56.10  600.000   16.263 0.008
2003-03-30T05:19:08.50  480.000   16.321 0.010
2003-03-30T06:21:03.50  480.000   16.415 0.006
2003-03-30T07:24:03.20  480.000   16.510 0.004
2003-03-30T08:01:23.30  480.000   16.577 0.004
2003-03-30T08:50:07.70  480.000   16.648 0.004
2003-03-30T09:38:09.20  480.000   16.712 0.005
2003-03-30T10:38:02.00  480.000   16.889 0.013


V data:

2003-03-30T04:50:46.60  600.000   15.8732 0.011
2003-03-30T05:27:41.40  480.000   15.9492 0.007
2003-03-30T06:29:52.70  480.000   16.0532 0.007
2003-03-30T07:34:17.30  480.000   16.1452 0.004
2003-03-30T08:10:09.80  480.000   16.1642 0.041
2003-03-30T08:58:43.00  480.000   16.2722 0.004
2003-03-30T10:07:14.90  480.000   16.3632 0.005
2003-03-30T10:49:03.60  480.000   16.4142 0.007


R data:

2003-03-30T04:13:44.60  600.000   15.402 0.006
2003-03-30T05:01:52.70  480.000   15.524 0.007
2003-03-30T06:38:59.40  480.000   15.694 0.009
2003-03-30T07:43:11.40  480.000   15.801 0.004
2003-03-30T08:18:47.30  480.000   15.841 0.005
2003-03-30T09:07:42.20  480.000   15.917 0.004
2003-03-30T10:16:32.90  480.000   16.004 0.006
2003-03-30T10:58:45.90  480.000   16.048 0.006


I data:

2003-03-30T04:29:03.70  600.000   15.0006 0.009
2003-03-30T05:10:35.20  480.000   15.1076 0.012
2003-03-30T06:47:29.70  480.000   15.2816 0.007
2003-03-30T07:52:23.00  480.000   15.3916 0.004
2003-03-30T08:27:17.40  480.000   15.4266 0.027
2003-03-30T09:16:35.30  480.000   15.5186 0.005
2003-03-30T10:26:31.30  480.000   15.6376 0.008
2003-03-30T11:07:31.20  480.000   15.7036 0.011


-------------------------------------------------------------------------
                             Jerome A. Orosz
      Assistant Professor of Astronomy, San Diego State University
             5500 Campanile Drive, San Diego, CA 92182-1221
(619) 594-7118 (office), 594-6182 (dept. secretary), 594-1413 (dept. fax) 
               http://mintaka.sdsu.edu/faculty/orosz/web/

J. Tober, E. Hoverstein, K. Chiu, K. Glazebrook

We have observed the optical afterglow of GRB 030329 with the 20in 
Morris W. Offit telescope
of the Maryland Space Grant Consortium Observatory. The telescope is 
located in
downtown Baltimore, Maryland and the observations were made with a 
student built
CCD camera on the night of March 31st / morning of April 1st with an 
R-band filter.

Aperture photometry was made with APPHOT in a 20 arcsec diameter 
aperture with
errors empirically estimated from the background noise. The photometry 
is
computed by assuming the USNO reference star at RA 10 44 42.01 DEC +21 
32 31.8
has constant magnitude R=16.2 but counts were consistent from run to run
indicating near-photometric conditions.

The GRB appeared to brighten suddenly between ~02:30 and ~03:30 by 0.5 
mags and then fade
slowly for the next few hours.

Table 1. R-band Observations. Magnitudes and errors. Times (t) are in 
minutes from 02:33 UT on
April 01, 2003 and refer to the middle of stacked sequences of ~25 
minute exposures.

   t   Star1         Star3        Star5         GRB

   0   13.749 0.007 16.257 0.069 16.904 0.126  17.457  0.207

  52   13.696 0.007 16.104 0.064 16.617 0.108  16.844  0.130   *** Jump ?

117   13.778 0.007 16.275 0.069 16.931 0.128  17.056  0.141

165   13.826 0.007 16.198 0.062 16.884 0.108  17.169  0.154

209   13.637 0.008 16.076 0.070 16.538 0.104  16.940  0.153

The error on the reference star was +/- 0.07 which should be added in 
quadrature to
the above table.

(Note star 1 is off the nominal R=14.00 value which we attribute to 
non-linearity in the CCD)

This photometry is preliminary, further analysis is proceeding. The 
reference stars
are indicated at:

http://mrhanky.pha.jhu.edu/~kgb/GRB030329/grb-circ-finder.jpg

A plot of the light curve is available from:

http://mrhanky.pha.jhu.edu/~kgb/GRB030329/grbplot2.ps

The  Maryland Space Grant Consortium Observatory is supported by NASA's 
National
Space Grant College and Fellowship Program. Further information is 
available at:
http://henry.pha.jhu.edu/msgc/observatory.html

E.Pavlenko, V.Rumyantsev, O.Antoniuk, N.Primak  (CrAO) and A.Pozanenko (IKI)
report:

We continue to monitor the OT of GRB030329 (GCN  2005
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 , 2028
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 , 2050
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 ).

The OT found by Peterson and Price  (GCN 1985
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 )  was imaged Cassegrain 38-cm
telescope of CrAO.  Several 240 sec. exposures in  R (Johnson) spectral band
were obtained. Based on filed photometry by A. Henden (GCN 2023
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 )  we
estimate the OT magnitude as

Mid Time (UT)              exposure             OT (R)
Apr 1.8754                   4x240 sec       17.07+/-0.05

Also we refined our estimations of OT within March 29-31.

Cassegrain 38-cm (CCD SBIG ST-7):

JD Hel           UT             V                         R
52728.2526   29.7526    -                    14.03 +/- 0.03
52728.4934   29.9934 15.15 +/- 0.02   -
52728.5072   30.0072 15.22 +/- 0.04   -
52729.2689   30.7689    -                     16.44 +/- 0.04
52729.4301   30.9301    -                     16.40 +/- 0.06
52730.2435   31.7435    -                     16.92 +/- 0.04
52730.3868   31.8868    -                     16.90 +/- 0.08
52730.4023   31.9023    -                     16.91 +/- 0.06


This message may be cited.

GRB 030329: Observations with ANDICAM

J. S. Bloom (CfA), M. Buxton (Yale), C. Bailyn (Yale), P. G. Van
Dokkum (Yale), S. R. Kulkarni (Caltech) report:

"We observed the afterglow of GRB 030329 (GCN #1985
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 , GCN #1997
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 ), using
CTIO 1.3m + ANDICAM on 2003 April 1.15 UT in photometric conditions. The
OT was well detected in BVIJH at the following brightness levels:

                                              UT Start, Int Time
B = 17.671 +/- 0.031   tgrb - t = 2.6676 day (03:33:29, 600 sec)
V = 17.263 +/- 0.043   tgrb - t = 2.6761 day (03:45:52, 600 sec)
I = 16.482 +/- 0.056   tgrb - t = 2.6870 day (04:01:30, 600 sec)

Optical photometry was calibrated to the Henden secondary standards (GCN
#2023
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 ). Zeropoint systematics dominate the uncertainties. Magnitudes have
not been corrected for Galactic extinction. We intend to obtain an IR
zeropoint and IR secondary standards over the next few nights.

Assuming a negligible change in flux between observations, we find (V - I)
= 0.781 +/- 0.070, confirming the V-I color reported in Li et al. (GCN
#2064
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 ). We find (B - V) = 0.408 +/- 0.053, which is inconsistent with Li
et al, but consistent with the B-V color reported Fitzgerald & Orosz (GCN
#2056
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 )."

A color composite image of the field may be viewed at:
 http://http://www-cfa.harvard.edu/~jbloom/GRB/grb030329/

More information about ANDICAM can be obtained at:
 http://www.ctio.noao.edu/yale/parameters.html

This message can be cited.

M. Leake, M. Williams (Valdosta State University)
K. Lindsay, D. H. Hartmann (Clemson University), 

Report on behalf of a larger collaboration:

We observed the optical afterglow of GRB 030329,
(=H2656, Vanderspek et al. GCN 1997
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 ), identified
by Peterson & Price (GCN 1985
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 ) and Torii (GCN 1986
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 ),
in the Johnson B-Band with the SARA 0.9m telescope at 
KPNO. We obtained 30, 300s exposures.  Observations
began at 03:06:49UT, and ended at 05:39:50UT, on April
1st.  The obsevations were carried out under good 
seeing conditions.  Aperture photometry is being 
carried out, and further observations are planned. 

More information on the SARA Observatory
can be found at http://www.saraobservatory.org/.

This report may be cited.

J. Brodney Fitzgerald and Jerome A. Orosz (San Diego State
University) report:

We report additional observations of the field of GRB 030329 (Peterson
& Price, GCN 1985
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 ) made with the 1 meter telescope at SDSU's Mount
Laguna Observatory.  Images were taken in the Bessell B, V, R, and I
filters on the night of 2003 April 1 (UT) in photometric conditions.
The data were reduced and calibrated in the same manner as previously
reported (GCN 2056
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 ).  Our observations are summarized in the 4 tables
below.  The CCD images of the GRB field and some Landolt fields are
available upon request to orosz@sciences.sdsu.edu.

The eclipsing binary we reported on previously had a small secondary
eclipse (about 0.1 mag deep) centered near 8:15 on April 1 (UT).  If
the orbit is circular and if no eclipses were missed between March 31
and April 1, then the orbital period would be about 2.3 days.

Our GRB observations follow:

Table 1: B Observations:

  date-obs at start     exptime     mag      err
                         (sec)
-------------------------------------------------
2003-04-01T03:34:38.20  360.000   17.703    0.009
2003-04-01T04:02:57.00  300.000   17.719    0.009
2003-04-01T06:09:32.80  300.000   17.814    0.009
2003-04-01T06:35:53.40  300.000   17.831    0.010


Table 2: V Observations:

  date-obs at start     exptime     mag      err
                         (sec)
-------------------------------------------------
2003-04-01T03:42:54.40  360.000   17.2512   0.009
2003-04-01T04:08:36.40  300.000   17.2642   0.008
2003-04-01T06:21:45.30  240.000   17.3562   0.011
2003-04-01T06:41:38.50  180.000   17.3622   0.012
2003-04-01T08:04:22.70  240.000   17.4552   0.012
2003-04-01T08:19:48.70  240.000   17.4252   0.011
2003-04-01T08:32:34.30  180.000   17.4332   0.014
2003-04-01T09:29:10.60  240.000   17.4402   0.014
2003-04-01T09:43:29.20  300.000   17.4732   0.014
2003-04-01T10:02:22.20  300.000   17.4702   0.018
2003-04-01T10:20:19.60  300.000   17.4572   0.027


Table 3: R Observations:

  date-obs at start     exptime     mag      err
                         (sec)
-------------------------------------------------
2003-04-01T03:49:27.80  360.000   16.866    0.008
2003-04-01T04:14:10.50  300.000   16.861    0.007
2003-04-01T06:26:24.20  240.000   16.948    0.010
2003-04-01T06:45:24.30  180.000   16.970    0.011
2003-04-01T08:09:57.70  240.000   17.005    0.011
2003-04-01T08:24:45.80  180.000   17.001    0.011
2003-04-01T08:36:10.50  180.000   17.018    0.012
2003-04-01T09:34:02.60  240.000   17.061    0.013
2003-04-01T09:49:12.30  300.000   17.062    0.014
2003-04-01T10:08:02.00  300.000   17.082    0.017
2003-04-01T10:26:06.80  300.000   17.065    0.019


Table 4: I Observations:

  date-obs at start     exptime     mag      err
                         (sec)
-------------------------------------------------
2003-04-01T03:56:03.40  360.000   16.4346   0.009
2003-04-01T04:19:46.20  300.000   16.4386   0.011
2003-04-01T06:30:57.60  240.000   16.5396   0.013
2003-04-01T06:49:05.10  180.000   16.5636   0.013
2003-04-01T08:15:29.10  180.000   16.5816   0.015
2003-04-01T08:28:55.70  180.000   16.5746   0.016
2003-04-01T08:39:51.10  180.000   16.5726   0.015
2003-04-01T09:38:45.20  240.000   16.6346   0.019
2003-04-01T09:55:58.10  300.000   16.6586   0.020
2003-04-01T10:14:17.10  300.000   16.6826   0.027
2003-04-01T10:31:37.20  300.000   16.6636   0.025

-------------------------------------------------------------------------
                             Jerome A. Orosz
      Assistant Professor of Astronomy, San Diego State University
             5500 Campanile Drive, San Diego, CA 92182-1221
(619) 594-7118 (office), 594-6182 (dept. secretary), 594-1413 (dept. fax) 
               http://mintaka.sdsu.edu/faculty/orosz/web/

A. Price & J. Mattei (AAVSO) report on behalf of the AAVSO International
GRB Network:

The AAVSO International GRB Network has obtained additional B, V, and R
photometry of the afterglow to GRB030329 covering dates from March 29 to
April 1.

See notes for details, access to errors and time series data.

Zsolt Kereszty, 0.25m at Corona Borealis Observatory, Hungary
 B = 15.43 @ 2003.03.29 21:44
 B = 17.25 @ 2003.03.31 20:56
 V = 14.93 @ 2003.03.29 21:44
 V = 16.76 @ 2003.03.31 19:46
Rc = 14.53 @ 2003.03.29 21:44
Rc = 16.39 @ 2003.03.31 20:25
   exposures: 13X60s

Gilbert C. Lubcke, .28m at Wisconsin, USA
Rc = 15.23 @ 2003.03.30 01:46 to
Rc = 15.81 @ 2003.03.30 07:00
 V = 15.56 @ 2003.03.30 01:46 to
 V = 16.08 @ 2003.03.30 07:00
  exposures: 22X240s

Josch Hambsch and Eric Broens, .4m at Mol, Belgium (VVS Werkgroep
Veranderlijke Sterren)
Rs = 16.47 @ 2003.03.30 19:42 to
Rs = 16.40 @ 2003.03.30 21:55
 V = 16.84 @ 2003.03.30 19:56 to
 V = 16.68 @ 2003.03.30 22:06
 exposures: 15X300-600s
Rs = 16.79 @ 2003.03.31 19:04 to
Rs = 17.02 @ 2003.03.31 22:55
 V = 17.18 @ 2003.03.31 19:22 to
 V = 17.26 @ 2003.03.31 22:53
 exposures: 21X600s

Bjorn H. Granslo, .25m at Haagaar Observatory, Norway.
V = 16.8 @ 2003.03.30 20:49
 exposures: 6X150s

Peter Brown, 0.41m at Orson Pratt Observatory, Brigham Young
University, Utah USA
Rj = 15.14 @ 2003.03.30 02:32 to
Rj = 16.12 @ 2003.03.30 10:34
 V = 15.67 @ 2003.03.30 04:06 to
 V = 16.04 @ 2003.03.30 10:45

Dennis Hohman, .2m at Stone Edge Observatory, New York, USA
Rs = 16.27 @ 2003.03.31 01:53 
Rs = 16.35 @ 2003.03.31 02:12 
Rs = 16.48 @ 2003.03.31 03:29 
Rs = 16.28 @ 2003.03.31 04:31 
 V = 16.56 @ 2003.03.31 02:27 
 V = 16.75 @ 2003.03.31 03:47 
 V = 16.54 @ 2003.03.31 04:50
Rs = 16.72 @ 2003.04.01 01:45 
 V = 17.06 @ 2003.04.01 03:23 
  exposures: 9X180s

Dr. D. T. Durig and C. G. Achee, .3m at Cordell-Lorenz Observatory, 
Tennessee, USA.
Rc = 17.24 @ 2003.04.01 02:20
Rc = 17.24 @ 2003.04.01 02:40

Bill Aquino, 0.3m with Buffalo Astronomical Association in
New York, USA
V = 17.25 @ 2003.04.01 02:45
    exposures: 3X300s

* Rs is a filter designed by C. Schuler which follows Rc very closely.
* Times are midpoints
* Detailed reports (observing equipment, location, conditions, etc.)
and many original FITS files available at
ftp://ftp.aavso.org/grb/GRB030329 or by e-mailing aavso@aavso.org.
 * Lubcke, Hambsch et al., Granslo, Brown, Hohman, and Aquino
used Henden et al. photometry (GCN 2023
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 ) for comparison.  
Kereszty used comp star A described on the finder chart by
Rumyantsev et al. (GCN 2005
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 ) Durig et al. used comp star A
described on the finder chart by Martini et al.(GCN 2012
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 ).
 * Lubcke, Hambsch et al. and Brown have time series data
available.  These observations bracket their datasets.


  The CCD used by Kereszty plus other components of the AAVSO
International GRB network were funded by a generous grant from
the Curry Foundation.

The radio source associated with GRB030329 was observed
at 15.2 GHz with the Ryle Telescope (cf GCN 2043
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 ) on 
2003 Mar 31 - Apr 01 and Apr 01 - Apr 02.
The flux density during each observation was almost constant;
2003 Mar 31.91   18 mJy
2003 Apr 01.98   16 mJy.

A. Pramesh Rao and C. H. Ishwara Chandra (National Centre for Radio
Astrophysics, Pune, India), and D. Bhattacharya (Raman Research
Institute, Bangalore, India) report on behalf of a larger collaboration:

The GRB030329 was observed with the Giant Metrewave Radio Telescope
(Khodad, India) for 8 hours on 31 March and for 5 hours on 01 April 2003.
The observations were at 1288  MHz with a bandwidth of 8MHz and angular
resolution of ~3.5". There was a detection of emission at the position
of the GRB as shown below

   Date         Time		Flux Density     rms noise

31 March 2003  14-22 UT		245 microJy	35 microJy
01 April 2003  18-22 UT         235 microJy     40 microJy


It is at present unclear whether the detected flux is due to the burst or
due to a background source that may or may not be associated with the
burst.

A GMRT map of the field can be seen in

	http://www.ncra.tifr.res.in/~pramesh/images/grb030329.jpg

This message may be cited.

M. Cantiello, M. Dolci (INAF - Obs. of Teramo), E. Maiorano (Univ. Bologna
& IASF/CNR, Bologna), N. Masetti, E. Palazzi (IASF/CNR, Bologna), E.
Brocato (INAF - Obs. of Teramo) report:
 
"We have obtained BVRI images of the OT (Peterson & Price, GCN 1985
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 ) of
GRB030329 (Vanderspek et al., GCN 1997
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 ) with the 0.72-m TNT telescope of
the Astronomical Observatory of Teramo (Italy).
The average seeing was 4 arcsec.
 
The OT was well detected in all bands; we measure for it the following 
BVRI magnitudes using field stars calibrated by Henden (GCN 2023
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 ):

mid-exposure      exptime    filter     mag     err
 time (UT)           (s)
-------------------------------------------------------
 Apr. 1.824         1200        R       17.02    0.02
 Apr. 1.911         1800        V       17.53    0.03
 Apr. 1.966         2400        B       18.01    0.04
 Apr. 1.989         1200        I       16.70    0.03
 Apr. 2.055         1200        R       17.16    0.03
 
The comparison between the two R-band magnitude measurements shows that 
the OT has possibly faded across our observing run.
 
This message is citeable."

S. Zharikov (OAN SPM, IA UNAM, Mexico), E. Benitez, J. Torrealba, J.
Stepanian (IA UNAM, Mexico) report:

We have observed the GRB030329 OT with 1.5m and 2.1m
telescopes of SPM Observatory, BC, Mexico. A set of exposures in UBVRI
Bessel filters was obtained with 1.5m telescope under photometric
conditions. Standard stars RU 149  from Landolt's catalogue
were used for photometric calibrations.
The results of photometry are following:
 31 March   U      B     V     R      I
UT 7:00   16.62
UT 7:13         17.27
UT 7.16                16.90
UT 7:21                      16.46
UT 7:26                             16.11
UT 7:31  16:65
UT 7:37        17.28
UT 7:43               16.84
UT 7:49                     16.08
UT 7:54                             16.05
UT 8:48  16.58
UT 8:54        17.30
UT 8:59               16.92
UT 9:05                     16.51
UT 9:11                            16.11
UT10:08  16:59
UT10:13       17.27
UT10:19              16.83
UT10:60                    16:60
UT10:31                           16:22
Errors are about 0.03.

Spectrum of the optical afterglow of GRB 030329 were obtained at the 
same night with the 2.1-m telescope and B&Ch spectrograph (600l/mm).
The spectra cover the wavelength range of 6100 to 8200 AA with a
resolution of about 2.2A/pix.
The spectral data analysis is in progress.

This message may be cited.

M.A. Ibrahimov, I.M. Asfandiyarov, B.B. Kahharov (Ulugh Beg Astronomical
Institute of Uzbekistam Academy of Science), A.Pozanenko (IKI), V.Rumyantsev
(on behalf of CrAO GRB team), G.Beskin (SAO) report:


We have observed the OT found by Peterson and Price  (GCN 1985
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 ) of GRB030329
with  1.5m telescope of  High-altitude Observatory at Mt.Maidanak.  The
telescope is equipped   with  CCD SITe (2000x800). The observations were
carried out under good seeing conditions (1".0). Several BRI Bessel images
were obtained in April, 1. Based on star filed photometry by A. Henden (GCN
2023
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 )  we estimate the OT magnitude:

UT, Apr 1 filter  exposure  mag       err

18:42:24  R       300        17.082   0.021
18:48:06  R       300        17.036   0.025
18:53:48  B       600        17.707   0.072
19:04:35  R       300        16.977   0.044
19:10:09  R       600        17.016   0.027
19:20:52  I        600        16.625   0.047
19:31:41  R       600        17.045   0.047
19:44:55  R       600        17.010   0.033
19:56:01  B       600        17.766   0.031
20:14:49  B       300        17.777   0.013
20:20:28  R       300        17.022   0.011
20:26:26  I        300        16.520   0.013
20:32:10  B       300        17.799   0.015
20:37:58  R       300        17.030   0.011
20:43:39  I        300        16.531   0.013
20:52:03  B       600        17.741   0.029
21:02:42  R       300        17.006   0.023

The estimation is preliminary and may be improved.

This message may be cited.

Weidong Li, Ryan Chornock, Saurabh Jha, and Alexei V. Filippenko (UC Berkeley)
report:

We collected the available R-band measurements of the GRB 030329
afterglow through GCN 2077
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  and a table is available at
http://astron.berkeley.edu/~bait/grb/gcn030329.r.dat

We found that the afterglow went through at least three re-brightening
phases. A figure illustrating this can be found at
http://astron.berkeley.edu/~bait/grb/grb030329.p3.ps

The first re-brightening, as reported by Lipkin et al. (GCN 2045
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 ) and
Burenin et al (GCN 2046
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 ),  occurred at about 30 hours after the burst.
The second re-brightening, as reported by Lipkin et al. (GCN 2060
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 ), 
occurred at about 60 hours after the burst. A third re-brightening
occurred at about 80 hours after the burst. 

The afterglow appears to decline with a power law after each re-brightening.
The following power-law indices are measured for the three dashed lines
in our plot:

t = 16 to 30 hours:  alpha = -1.70 +/- 0.04
t = 40 to 60 hours:  alpha = -1.63 +/- 0.07
t = 64 to 70 hours:  alpha = -2.09 +/- 0.26

A preliminary analysis of the data reported in GCN Circulars
suggests that the afterglow shows the same behavior in the
other bands (BVI) as well, though the re-brightening episodes 
were less constrained than in the R band.

This message may be cited.

R. Burenin, R. Sunyaev, M. Pavlinsky, D. Denissenko, O. Terekhov,
A. Tkachenko (IKI); Z. Aslan, I. Khamitov, M. Parmaksizoglu (TUG);
U. Kiziloglu, A. Alpar, A. Baykal (METU); I. Bikmaev, N. Sakhibullin,
V. Suleymanov (KSU)

report:

We observed the GRB 030329 afterglow (Peterson and Price, GCN 1985
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 ) with
1.5-m Russian-Turkish Telescope RTT150 at Bakyrlytepe, in BVRI Bessel
filters. Assuming that the magnitude of "A" star is R=16.20, we measured
R=17.94 for UT= April 3.05 (109.5 hours after the burst).

This message may be cited.

R. Sato, Y. Yatsu, M. Suzuki, and N. Kawai (Tokyo Tech) report:

We have observed the afterglow (Peterson and Price GCN 1985
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 , Torii GCN
1986
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 ) of GRB030229 (H2652, Vanderspek et al. GCN 1997
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 ) on the nights
of 2003 Apr 29, 30, and 31 at Tokyo Tech, Tokyo, Japan, using a 30 cm
SC telescope with unfiltered AP 6E CCD camera.  The observationl
started at 12:57 UT (80 min after the GRB trigger).

We have estimated the R magnitude using USNO 2.0 stars U1050_06349885
(R=13.2), B:U1050_06348771 (R=14.2), and C:U1050_06351075 (R=14.0).
The results are shown in the table below.  The dip and rebrightening
at t0+1.2d (Lipkin et al. GCN 2045
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 ) was detected in our data too.

 t-t0 (days)    R mag   err

   0.0620      12.552  0.023
   0.1484      13.370  0.029
   0.1943      13.604  0.034
   0.2373      13.799  0.043
   0.2970      14.145  0.074
   0.9457      15.987  0.127 
   1.0151      16.167  0.081
   1.0936      16.504  0.125
   1.2172      16.316  0.140 
   2.0050      17.087  0.212
   2.1238      17.148  0.207

The images on the first night and our light curve can be found at
http://www.hp.phys.titech.ac.jp/nkawai/030329/index_e.html.

This message may be cited.

A. Zeh, S. Klose (Thueringer Landessternwarte Tautenburg),
J. Greiner (MPE Garching),

report:


Using the light curves of SN 1998bw (Galama et al. 1998, Nature 395,
670) as a template we have analyzed what color changes are expected to
be seen in the optical transient following GRB 030329 if a supernova
component would appear.


Ingredients:
------------

1) SN 1998bw:

- A_V = 0.20 mag (Woosley, Eastman, & Schmidt 1999, ApJ 516, 792)
- no time delay between the onset of the SN and the onset of the GRB
- A_V(host) = 0.0 mag


2) The host galaxy:

- z = 0.1685 (Greiner et al. 2003, GCN 2020
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 )
- a negligible host flux in BVRI (based on R>22.5; Blake & Bloom 2003,
  GCN 2011
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 )
- A_V(Galaxy) at (l, b) = 217.07, b = 60.68:
  E(B-V) = 0.025 (Schlegel, Finkbeiner, & Davis 1998, ApJ 500, 525),
- R_V = 3.1


3) The GRB afterglow:

- Considering published GCN R-band data, analyzed according to
  Beuermann et al. (1999, A&A 352, L26), we find:

  alpha_1 = 0.85 +/- 0.04
  alpha_2 = 1.55 +/- 0.02
  t_break = 0.42 +/- 0.03 days,

  after ignoring the several re-brightenings during the last days

- colors (best fit):
  B-V = 0.39 mag
  V-R = 0.34 mag
  R-I = 0.47 mag

- we have taken into account the latest re-brightening episode and assumed that
  a) alpha_2 remains constant and b) the color of the afterglow does not change


Output cocktail:
----------------

 - Fig. 1: the light curve
 - Fig. 2: the expected color evolution

We note that differences in the reported value for alpha_2 (cf. Li
et al. 2003, GCN 2078
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 ) can be explained by slightly different
selection criteria for the data chosen to perform the numerical fit.

http://www.tls-tautenburg.de/research/klose/grb.html


Warning:
--------

These results are based on a simple toy model. They provide only a
hint about what the strength of the SN signal could be since most
SN bumps found so far had a brightness of only 30-80% of SN 1998bw.

A. Henden (USRA/USNO) reports on behalf of the USNO GRB team:

We have acquired additional UBVRcIc all-sky photometry for
an 11x11 arcmin field centered at the coordinates
of the optical transient (Peterson and Price, GCN 1985
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 )
for the HETE burst GRB030329 (GCN 1997
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 ) with the USNOFS
1.0-m telescope.  Stars brighter than V=13.5 are saturated and
should be used with care.  We have replaced the photometric data
with the same file name on our anonymous ftp site:
ftp://ftp.nofs.navy.mil/pub/outgoing/aah/grb/grb030329.dat
The astrometry in this file is based on linear plate solutions
with respect to UCAC2.  The external errors are less than 100mas.
The second night of photometry shows that the first night was
acceptable, and that the external error is now about 0.02mag.
     For those of you not used to doing high-accuracy
photometry, here are some comments.  Star "A" of Martini et al.
(GCN2012
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 ) has been used with either its USNO-A magnitude of
R=16.2, or the more correct Rc=16.06, in various GCNs.  This
will lead to confusion when trying to fit light curves.  However,
the larger problem is that this star is red (B-V=1.19,
V-I=1.41), while the afterglow itself is blue (B-V=0.35,
V-I=0.77).  Using this star as a comparison and following
it over a large airmass will generally lead to fading/brightening
trends that correlate with airmass due to differential
color corrections unless proper transformations are made.
This will be even more apparent when comparing Johnson R,I
magnitudes with the Cousins Rc,Ic values reported here.
You should also be aware of the nice eclipsing binary discovered
by Fitzgerald and Orosz (GCN 2056
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 ), as this is the brightest
object near the afterglow and might be used when performing
early-time photometry or U-band photometry.  Finally, as
several observers have mentioned, there are not many real stars
in this field; most of the objects are extended.  You should
look at the good-seeing finding charts that have been posted
before selecting comparison stars, especially as the afterglow
fades.  Many extended objects are near-enough to stellar that
they will appear in our field photometry file.

We intend to extend this file with more nights and to fainter
magnitudes as the afterglow fades.  As always, you should check
the dates on the .dat file prior to final publication to get the
latest photometry.

E.Pavlenko, V.Rumyantsev, O.Antoniuk, N.Primak  (CrAO) and A.Pozanenko (IKI)
report:

We continue to monitor the OT of GRB030329 (see also GCN  2005
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 , 2028
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 , 2050
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 ,
2067
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 ).

The OT found by Peterson and Price  (GCN 1985
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 )  was imaged Cassegrain 38-cm
telescope of CrAO.  Several 300 sec. exposures in  R (Johnson) spectral band
were obtained during Apr. 2. Based on filed photometry by A. Henden (GCN
2023
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 )  we estimate the OT magnitude:

Mid time              exposure     R
(UT)

2.7648                 5x300c       17.83  +/- 0.08
2.7929                 5x300c       17.76  +/- 0.08
2.8436                 5x300c       17.89  +/- 0.07
2.8739                 5x300c       17.76  +/- 0.09

After steep decay between  Apr 1. and  Apr. 2 we observed a flattening of
light curve which may be a start of new episode of re-brightening.

This message may be cited.

M.A. Ibrahimov, I.M. Asfandiyarov, B.B. Kahharov (Ulugh Beg Astronomical
Institute of Uzbekistam Academy of Science), A.Pozanenko (IKI), V.Rumyantsev
(on behalf of CrAO GRB team), G.Beskin (SAO) report:


We have observed the OT found by Peterson and Price  (GCN 1985
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 ) of GRB030329
with  1.5m telescope of  High-altitude Observatory at Mt.Maidanak.   The
observation is carrying under good seeing conditions. Using star filed
photometry by A. Henden (GCN2023
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 )  we obtained  a prelimiary estimation of
the OT magnitude:

UT, Apr. 3    filter  exposure  mag
Mid time

15:34:12       R       300        17.80
15:42:58       R       600        17.84

with a typical error ~ 0.05

Taking into account  the data of   R. Burenin et al. (GCN 2079
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 ) and
E.Pavlenko et al. (GCN 2083
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 ) one can suggest that the re-brightening took
place with a maximum early Apr. 3.

This message may be cited.

M. Leake, M. Williams (Valdosta State University)
K. Lindsay, D. H. Hartmann (Clemson University), 

Report on behalf of a larger collaboration:

We observed the optical afterglow of GRB 030329,
(=H2656, Vanderspek et al. GCN 1997
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 ), identified
by Peterson & Price (GCN 1985
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 ) and Torii (GCN 1986
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 ),
in the Johnson B-Band with the SARA 0.9m telescope at 
KPNO. We obtained 30, 300s exposures.  Observations
began at 03:30:39UT, and ended at 06:15:07UT, on April
2nd.  The obsevations were carried out under partial
cloud cover and relatively windy conditions.  
Aperture photometry is being carried out, and further 
observations are planned. 

More information on the SARA Observatory
can be found at http://www.saraobservatory.org/.

This report may be cited.

K. Lindsay (Clemson University) 

Report on behalf of a larger collaboration:

We observed the optical afterglow of GRB 030329,
(=H2656, Vanderspek et al. GCN 1997
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 ), identified
by Peterson & Price (GCN 1985
Loading...
 
 ) and Torii (GCN 1986
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 ),
in the Johnson B-Band with the SARA 0.9m telescope at 
KPNO. We obtained 28, 300s exposures.  Observations
began at 02:56:23UT, and ended at 05:16:54UT, on April
3rd.  The obsevations were carried out under 
relatively windy conditions.  Aperture photometry is 
being carried out, and further observations are planned. 

We thank SARA observer Dr. Scott Shaw for making part 
of his observing time available to us.

More information on the SARA Observatory
can be found at http://www.saraobservatory.org/.

This report may be cited.

Jim C. Hoge (JCMT), Rowin Meijerink (Leiden Observatory),
Remo P.J. Tilanus (JCMT), and Ian A. Smith (Rice University)
report on behalf of the NL JCMT collaboration:

We have observed the afterglow of GRB 030329 (GCN 1985
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  and 
following) using the SCUBA sub-millimeter continuum bolometer 
array on the James Clerk Maxwell Telescope located on Mauna 
Kea, Hawaii.  The observations took place on 2003 Apr 03.4 UT.

Although the conditions were not very good, the source was 
easily detected.  Preliminary calibration gives an 850 micron 
flux density of 30 +/- 5 mJy.

Further observations are planned.

N. Kuno, N. Sato, and H. Nakanishi(NRO) report:

We have observed the radio afterglow (GCN 2014
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 , 2043
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 ) of GRB 030329
(GCN 1997
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 ) with the Nobeyama 45 m radio telescope, Japan 
from 2003 Apr 3 11:03 UT to 17:00 UT.  The mean flux densities are:

 23 GHz        32.2 +- 0.9 mJy
 43 GHz        53.9 +- 2.9 mJy
 90 GHz        80.4 +- 5.6 mJy

We will continue monitoring if the weather condition permits.

This message may be cited.

Two further 15.2-GHz observations of GRB030329 with the Ryle Telescope
yield the following flux densities:

2003 Apr 03.07  20 mJy
2003 Apr 04.11  28 mJy

V. Lipunov, A. Krylov, V. Kornilov, G. Borisov, D. Kuvshinov, A. Belinski,
I. Chilingarian, M. Kuznetsov, S. Potanin, V. Vitrischak, G. Antipov

Sternberg Astronomical Institute, Alexsandr Krylov Observatory, Moscow

report:

The OT of GRB030329 (Peterson and Price, GCN 1985
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 ) was observed by MASTER
system (Lipunov et al., GCN 2002
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 , GCN 2035
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 ). Here we represent pre-final
light curve of the OT. We used more than 200 direct images to obtain field
photometry. Several groups of images were summarized to achieve better
S/N ratio and smaller uncertanities of measurements. As the final result, we
represent 64 points. Magnitude calibration was made according to the data,
presented in GCN 2023
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  (A. Henden). 4 stars were used to do the calibration.

Big uncertanities of magnitude measurements are caused by weather
conditions. First points were made just after sunset on the blue sky, last
points were made through cirruses near the horizont.

From these data we obtained new power law flux decreasing during
8 hours of observations (t-t0 from 5.2h to 13.5h):

F ~ t^(-alpha), alpha=1.22+-0.03
Rmag = 15.8 + 1.2*2.5*log(age in days)

New light curve plots available at old locations:
http://observ.pereplet.ru/images/GRB030329_R_lc.gif
http://www.sai.msu.su/~chil/GRB030329_R_lc.ps

  date       UT      t-t0,hrs       R    errR
03/29/2003 16:51:49   5.24691    13.744  0.417
03/29/2003 16:54:27   5.29080    13.934  0.409
03/29/2003 17:02:12   5.41997    13.702  0.226
03/29/2003 17:07:36   5.50997    14.012  0.211
03/29/2003 17:12:04   5.58441    13.708  0.164
03/29/2003 17:14:29   5.62469    13.854  0.151
03/29/2003 17:19:18   5.70497    13.983  0.097
03/29/2003 17:34:11   5.95302    14.118  0.172
03/29/2003 17:36:19   5.98858    13.908  0.103
03/29/2003 17:40:01   6.05024    13.972  0.101
03/29/2003 17:42:44   6.09552    14.043  0.079
03/29/2003 17:46:24   6.15663    14.004  0.081
03/29/2003 17:49:09   6.20247    14.007  0.078
03/29/2003 17:52:18   6.25497    13.971  0.083
03/29/2003 17:55:22   6.30608    13.943  0.073
03/29/2003 17:59:49   6.38024    14.092  0.085
03/29/2003 18:11:56   6.58219    14.007  0.125
03/29/2003 18:21:10   6.73608    14.126  0.111
03/29/2003 18:40:45   7.06247    14.180  0.083
03/29/2003 18:43:29   7.10802    14.145  0.085
03/29/2003 18:46:06   7.15163    14.090  0.083
03/29/2003 18:48:46   7.19608    14.169  0.085
03/29/2003 18:51:23   7.23969    14.147  0.087
03/29/2003 18:54:06   7.28497    14.128  0.085
03/29/2003 18:56:48   7.32997    14.254  0.088
03/29/2003 18:59:29   7.37469    14.175  0.084
03/29/2003 19:02:06   7.41830    14.231  0.089
03/29/2003 19:04:48   7.46330    14.141  0.080
03/29/2003 19:07:29   7.50802    14.325  0.098
03/29/2003 19:12:54   7.59830    14.216  0.101
03/29/2003 19:15:32   7.64219    14.261  0.098
03/29/2003 19:18:10   7.68608    14.070  0.088
03/29/2003 19:21:27   7.74080    14.168  0.121
03/29/2003 19:52:30   8.25830    14.395  0.108
03/29/2003 19:55:12   8.30330    14.375  0.105
03/29/2003 19:58:05   8.35136    14.450  0.101
03/29/2003 20:00:50   8.39719    14.431  0.110
03/29/2003 20:03:42   8.44497    14.336  0.094
03/29/2003 20:08:30   8.52497    14.499  0.097
03/29/2003 20:11:15   8.57080    14.318  0.100
03/29/2003 20:14:05   8.61802    14.463  0.100
03/29/2003 20:16:50   8.66386    14.324  0.093
03/29/2003 20:19:28   8.70774    14.432  0.099
03/29/2003 20:24:45   8.79580    14.440  0.061
03/29/2003 20:36:35   8.99302    14.541  0.075
03/29/2003 20:41:20   9.07219    14.515  0.075
03/29/2003 20:45:58   9.14941    14.437  0.074
03/29/2003 20:51:17   9.23802    14.514  0.080
03/29/2003 20:56:44   9.32886    14.644  0.092
03/29/2003 21:01:30   9.40830    14.578  0.092
03/29/2003 21:07:22   9.50608    14.458  0.087
03/29/2003 21:17:37   9.67691    14.557  0.079
03/29/2003 21:28:18   9.85497    14.604  0.079
03/29/2003 21:39:07  10.03524    14.740  0.078
03/29/2003 21:49:59  10.21636    14.616  0.065
03/29/2003 22:03:48  10.44663    14.698  0.070
03/29/2003 22:16:04  10.65108    14.493  0.068
03/29/2003 22:26:44  10.82886    14.719  0.080
03/29/2003 22:41:42  11.07830    14.632  0.089
03/29/2003 23:03:55  11.44858    14.854  0.113
03/29/2003 23:35:46  11.97941    14.905  0.117
03/30/2003 00:04:04  12.45108    14.859  0.090
03/30/2003 00:23:25  12.77358    14.837  0.129
03/30/2003 00:52:04  13.25108    15.064  0.162
03/30/2003 01:12:16  13.58774    15.002  0.161
03/30/2003 01:35:52  13.98108    15.594  0.413

We thank Sergey M. Bodrov (general director of optical company "Ochkarik")
for financial and equipment support of MASTER research project.

This message may be cited.

A. Henden (USRA/USNO), B. Canzian (USNO), H. Harris (USNO)
and T. Tilleman (USNO) report on behalf of the USNO GRB team:

We have acquired time-series UBVRcIc photometry of the optical transient
(Peterson and Price, GCN 1985
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 ) for the HETE burst GRB030329 (GCN 1997
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 )
with the USNOFS 1.0m and 1.3m telescopes on all nights since the
burst.  Photometric accuracy has been typically 0.01-0.02mag
in all colors (nice to have a bright OT!).
   On the last two nights, 030403 and 030404 UT, the transient
has ceased fading, with mean magnitude on 030403 of
V=18.16 and on 030404 of V=18.13.  This unusual behavior
may be the beginning of the supernova bump predicted by
Zeh et al. (GCN 2081
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 ), though there has not been strong
color evolution.

K. Krisciunas (OCIW/CTIO), T. Matheson, K.Z. Stanek (CfA),
    and P. Garnavich (Notre Dame)

We obtained spectra of four bright galaxies within 90 arcseconds
of the afterglow of GRB 030329 using the Magellan 6.5-m Clay
telescope and LDSS2 image/spectrograph. The data were taken
April 2 and 3 (UT). Emission lines of Halpha, [OIII] and [OII]
were detected in all four galaxies and their redshifts are:

 Galaxy      RA (2000) Dec       Sep. from GRB       z
   A     10:44:50.5 +21:32:05        47"           0.136   
   B     10:44:48.7 +21:31:39        28"           0.136    
   C     10:44:47.9 +21:31:04        33"           0.137    
   D     10:44:53.6 +21:30:11        84"           0.057    

The three observed galaxies closest to the burst appear to form a
small group at z=0.136 which is slightly foreground to the host
at z=0.168 (Greiner et al., GCN 2020
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 ; Caldwell et al. GCN 2053
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 ).

A finder chart for these galaxies can be found at:
 http://www.nd.edu/~pgarnavi/grb030329_galaxies.jpg

This message may be cited.

I. Khamitov, Z. Aslan, O.Golbasi, M.Parmaksizoglu (TUG)
I. Bikmaev, N. Sakhibullin, V. Suleymanov (KSU)
R. Burenin, R. Sunyaev, D. Denissenko, M. Pavlinsky,  O. Terekhov, 
A. Tkachenko (IKI); U. Kiziloglu, A. Alpar, A. Baykal (METU); 

report:

We continue observations of the GRB 030329 optical afterglow (Peterson
and Price, GCN 1985
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 ) with 1.5-m Russian-Turkish Telescope RTT150
at Bakyrlytepe. Star "A" has been used with magnitude Rc=16.06 (Henden, 
GCN 2082
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 ).  
We have measured the following magnitudes:

t-t0,hours       UT       R	Rerr
150.3     April 4.73     18.06	0.04

Afterglow continues to be bright.
This message may be cited.

B. C. Lee, D. Q. Lamb, D. L. Tucker and S. Kent on behalf of the SDSS
GRB team, report:

The optical transient associated with GRB 030329 (Peterson and Price,
GCN 1985
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 ; K. Torii, GCN 1986
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 ) was observed with the SDSS 0.5m
"Photometric Telescope" (PT) at two epochs, starting March 31.181 UT
and April 01.153 UT.  The preliminary r-band magnitude at March 31.181
UT was observed to be 16.60 +/- 0.02, and the u g r i z data on that
date is well fit by a flux power law of approximately nu^-0.94, or
nu^-1.0 if a reddening of E(B-V)=0.025 is applied (Bloom, GCN 2011
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  and
Schlegel et al. 1998).  The April 01 UT images are still being
processed.

Our ugriz photmetric catalog of other objects in the field will be 
made available upon request; please email bclee@lbl.gov or visit the 
follwing web page:

   http://supernova.lbl.gov/~bclee/grb/

This message may be cited.

B. C. Lee, D. Q. Lamb, D. L. Tucker and S. Kent on behalf of the SDSS
GRB team, report:

The optical transient associated with GRB 030329 (Peterson and Price,
GCN 1985
Loading...
 
 ; K. Torii, GCN 1986
Loading...
 
 ) was observed with the SDSS 0.5m
"Photometric Telescope" (PT) at two epochs, starting March 31.181 UT
and April 01.153 UT.  The preliminary r-band magnitude at March 31.181
UT was observed to be 16.60 +/- 0.02, and the u g r i z data on that
date is well fit by a flux power law of approximately nu^-0.94, or
nu^-0.85 if a reddening of E(B-V)=0.025 is applied (Bloom, GCN 2011
Loading...
 
  and
Schlegel et al. 1998).  The April 01 UT images are still being
processed.

Our ugriz photmetric catalog of other objects in the field will be 
made available upon request; please email bclee@lbl.gov or visit the 
follwing web page:

   http://supernova.lbl.gov/~bclee/grb/

This message may be cited.

E.Pavlenko, V.Rumyantsev, O.Antoniuk, N.Primak  (CrAO) and A.Pozanenko (IKI)
report:

The OT found by Peterson and Price  (GCN 1985
Loading...
 
 )  was imaged Cassegrain 38-cm
telescope of CrAO.  Several 300 sec. exposures in  R (Johnson)  obtained
during Apr. 4.  Based on filed photometry by A. Henden (GCN 2023
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 )  we
estimate the OT magnitude:

Mid time                      exposure       R
(UT)

 Apr 4.7686                  4x300c        18.12 +/-0.11
       4.8236                  5x300�        18.32 +/-0.10
       4.8412                  5x300c        18.04 +/-0.07

After nearly flat period between end of 030402 and end of 030403 (GCN
2083
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 ,2084
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 ,2092
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 ) the OT definitely start  a new fading phase. A power-law
index between Apr 3.8160 and  Apr 4.8049  can be estimated as alpha ~1.7

A 10x180 sec. exposure image obtained on April 04.8012 can be found in
http://grb.rssi.ru/GRB030329/030329_030404_at64.gif

This message may be cited.

M.A. Ibrahimov, I.M. Asfandiyarov, B.B. Kahharov (Ulugh Beg Astronomical
Institute of Uzbekistam Academy of Science), A.Pozanenko (IKI), V.Rumyantsev
(CrAO), G.Beskin (SAO)  on behalf of large collaboration report:

We have observed the OT found by Peterson and Price  (GCN 1985
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 ) of GRB030329
with  1.5m telescope of  High-altitude Observatory at Mt.Maidanak. Several
BVRI Bessel images were obtained on April, 3. Based on star filed photometry
by A. Henden (GCN 2023
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 )  we refined the estimation reported in GCN 2084
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  and
report new measurements:


UT, Apr 3   filter exposure, s  mag     err

15:31:56    R      300          17.842  0.018
15:38:12    R      600          17.853  0.013
18:40:49    R      600          17.787  0.027
18:52:27    R      600          17.830  0.015
19:03:13    R      600          17.766  0.013
19:14:07    B      600          18.483  0.015
19:25:11    V      600          18.126  0.015
19:35:55    R      600          17.832  0.014
19:46:45    I      600          17.299  0.020
19:58:36    B      600          18.577  0.018
20:09:46    V      600          18.109  0.016
20:20:26    R      600          17.801  0.014
20:31:14    I      600          17.333  0.023
20:41:54    R      600          17.805  0.018
20:52:38    R      600          17.806  0.014


This message may be cited.

A. Henden (USRA/USNO) reports on behalf of the USNO GRB team:

   We previously reported (GCN 2092
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 ) a cessation of fading.
As Pavlenko et al. (GCN 2097
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 ) recently reported, this standstill
has ended. Our data from last night (030405UT) indicates a typical
V magnitude of 18.7 and the light curve now fits on the power law from
nights prior to the standstill.  The standstill was approximately 0.4mag
deviant from the power law, the one of the largest bumps so far
for this afterglow.  Due to the shortness of the standstill and
the lack of color evolution, this was not likely to have been the
predicted SNe bump.

K. Lindsay (Clemson University) 

Report on behalf of a larger collaboration:

We observed the optical afterglow of GRB 030329,
(=H2656, Vanderspek et al. GCN 1997
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 ), identified
by Peterson & Price (GCN 1985
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 ) and Torii (GCN 1986
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 ),
in the Johnson B-Band with the SARA 0.9m telescope at 
KPNO. We obtained 28, 300s exposures.  Observations
began at 02:42:47UT, and ended at 05:13:30UT, on April
4th.  The obsevations were carried out under good 
seeing conditions.  Aperture photometry is being 
carried out, and further observations are planned. 

We thank SARA observer Dr. Scott Shaw for making part 
of his observing time available to us.

More information on the SARA Observatory
can be found at http://www.saraobservatory.org/.

This report may be cited.

K. Lindsay (Clemson University) 

Report on behalf of a larger collaboration:

We observed the optical afterglow of GRB 030329,
(=H2656, Vanderspek et al. GCN 1997
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 ), identified
by Peterson & Price (GCN 1985
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 ) and Torii (GCN 1986
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 ),
in the Johnson B-Band with the SARA 0.9m telescope at 
KPNO. We obtained 30, 300s exposures.  Observations
began at 03:03:38UT, and ended at 05:32:40UT, on April
5th.  The obsevations were carried out under good
seeing conditions.  Aperture photometry is being 
carried out, and further observations are planned. 

We thank SARA Observatory director Dr. Jim Webb, and
FIU graduate student Emily Howard for making part of 
their observing time available to us.

More information on the SARA Observatory
can be found at http://www.saraobservatory.org/.

This report may be cited.

V.Metlov (Crimean Laboratory of the Sternberg Astronomical Institute,
Moscow State University) report:
I have made photographic observations of the GRB030329 OT found by B.A.Peterson
and P.A.Price (GCN 1985
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 ) with 50-cm Maksutov telescope in Crimea.
Exposures: 60 minutes and 50 minutes in B and V filters accordingly.
Based on filed photometry presented in GCN 2023
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  by A.Henden (12 stars were used 
to do the calibration) I estimate the OT magnitudes:

UT, Apr 2		filter	  mag	 err

19:33:00 - 20:33:00       B      18.15   0.15
20:45:00 - 21:35:00       V      18.10   0.25

This message may be cited.

                                 Yours sincerely,
                                 V.G.Metlov

[GCN OPS NOTE (05apr03): This circular was delayed 35 hours due to no entry
in the valid list.]

A. Price, B. Monard, A. Oksanen, T. DiLapo, D. West, D. Kaiser, D.
Starkey, P. Nelson, P. P��kk�nen and J. Mattei (AAVSO); T. Durig, A. L.  
Seifert, C. B. Norton, G.F. Garland, J.K.Cole, J.B. Cherry (University of
the South); A. Henden (USRA/USNO)  report on behalf of the AAVSO
International GRB Network:

This is a 3rd set of observations of the OT found by Peterson and Price
(GCN 1985
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 ) dating from March 29th to April 6th.  Included in the
observations is a URL where a full report (equipment, seeing, etc.) is
available. Many times the original FITS image is also available. When time
series data is available we only put the first and last observation.

A light curve of all AAVSO data to date has been made by B. Gary and
posted at http://www.aavso.org/grb/grb030329.jpg


Bruce L. Gary, .25m at Arizona, USA.
Rc = 15.67 +/- 0.04 @ 2003.03.30 07:08 to
Rc = 16.82 +/- 0.04 @ 2003.03.30 04:26
 V = 15.89 +/- 0.06 @ 2003.03.30 07:16 to
 V = 16.13 +/- 0.04 @ 2003.04.01 08:38
Rc = 18.07 +/- 0.05 @ 2003.04.05 03:49
Rc = 18.78 +/- 0.12 @ 2003.04.06 03:50
     exposures:64X15s,70X30s(for last obs)
     ftp://ftp.aavso.org/grb/GRB030329/BruceL.Gary_GRB030329_2452731.81361_.txt

Arto Oksanen, .4m at Nyrola Observatory, Finland.
Rc = 16.714 merr: 0.051 @ 2003.03.31 19:09 to
Rc = 16.842 merr: 0.060 @ 2003.04.01 00:59
 V = 17.157 merr: 0.053 @ 2003.03.31 19:48 to
 V = 17.297 merr: 0.077 @ 2003.04.01 00:55
Rc = 18.59  merr: 0.04  # 2003.04.05 21:35
   exposures: 78x240s, 34x240s (last obs)
   ftp://ftp.aavso.org/grb/GRB030329/arto-030329-2nreport.txt
   http://nyrola.jklsirius.fi/grb/grb030329/

Tristan DiLapo, .31m at Orbit Jet Observatory, New York, USA.
Rc = 16.32 err: 0.06 @ 2003.03.31 02:56 to
Rc = 16.34 err: 0.06 @ 2003.03.31 04:02
  exposures: 10X120s
  ftp://ftp.aavso.org/grb/GRB030329/TristanDiLapo_GRB030329_2452732.28043_.txt

Doug West, .2m at West Skies Observatory, Kansas, USA.
Unfiltered = 17.2 +/- 0.14 2003.04.02 02:08  7*30s exposures
Unfiltered = 17.5 +/- 0.13 2003.04.04 02:09  14*35s exposures
Unfiltered = 18.3 +/- 0.20 2003.04.05 02:11  19X35s exposures
   exposures: 7X30s
   ftp://ftp.aavso.org/grb/GRB030329/west-grb030329.txt

Dan Kaiser, .35m at Crescent Moon Observatory, Indiana, USA.
Rc = 17.44 @ 2003.04.02 02:13
   exposures: 14X240s
   ftp://ftp.aavso.org/grb/GRB030329/kaiser-grb030329.txt

D. T. Durig, A. L. Seifert, C. B. Norton, G.F. Garland, J.K.Cole,
J.B. Cherry, .3m at Cordell-Lorenz Observatory, Tennessee, USA
Rc = 17.96 @ 2003.04.02 02:36
Rc = 18.06 @ 2003.04.02 03:38
Rc = 18.36 +/- 0.2 @ 2003.04.03 03:45
Rc = 18.46 +/- 0.2 @ 2003.04.03 03:59
     exposures: 4X600s
     ftp://ftp.aavso.org/grb/GRB030329/DrDouglasT.Durig_GRB030329_2452732.69648_.txt

Donn Starkey, .36m at DeKalb Observatory, Indiana, USA.
Rc = 16.06 @ 2003.04.02 04:30
Bu = 18.02 @ 2003.04.02 05:44
 V = 16.85 @ 2003.04.02 04:52
   ftp://ftp.aavso.org/grb/GRB030329/DonnStarkey_GRB030329_2452731.82174_.txt

Peter Nelson, .32m at Ellinbank Observatory, Australia.
Rc = 18.3 +/- 0.3 @ 2003.04.03 13:00
     exposures: 3X300s
     ftp://ftp.aavso.org/grb/GRB030329/PeterNelson_GRB030329_2452734.05919_.txt

Pertti P��kk�nen, .5m at Jakokoski Observatory, Finland.
Rg = 18.55 +/- 0.04 @ 2003.04.05 22:12
     exposures: 33X300s
     ftp://ftp.aavso.org/grb/PerttiP��kk�nen_GRB030329_2452736.16987_.txt
     http://cc.joensuu.fi/seulaset/ccd/20030405/

Correction: The data below is a recalculation (based on a better comp
 star) of data posted earlier in GCN 2058
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 .
Berto Monard, .3m at Bronberg Observatory. South Africa
Unfiltered: 13.8 @ 2003.03.29 17:15 to
Unfiltered: 14.7 @ 2003.03.29 23:37
ftp://ftp.aavso.org/grb/GRB030329/monard-GRB030329mar29.txt

 * Durig et al., Gary, Starkey, Oksanen, West, Nelson, P��kk�nen and
Kaiser used Henden et al. photometry (GCN 2023
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 ) for comparison. DiLapo
used USNOA2. Monard used Tycho-2.

 * P��kk�nen's R filter (Rg) is a custom designed filter. Info at:
http://cc.joensuu.fi/seulaset/ccd/rgbfilters.png

 The AAVSO International GRB network is greatful for a generous grant from
the Curry Foundation and to NASA for the financial support for the High
Energy Workshops for Amateur Astronomers.

I. Khamitov,  M.Parmaksizoglu (TUG);
I. Bikmaev, N. Sakhibullin, V. Suleymanov, R.Gumerov, A.Ibragimov (KSU);
Z. Aslan, O.Golbasi (TUG);
R. Burenin, R. Sunyaev, D. Denissenko, M. Pavlinsky,  O. Terekhov, A. 
Tkachenko (IKI); 
U. Kiziloglu, A. Alpar, A. Baykal (METU); 

report:

We continue observations of the GRB 030329 optical afterglow (Peterson
and Price, GCN 1985
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 ) with 1.5-m Russian-Turkish Telescope RTT150
at TUG. 

Using stars from Henden (GCN 2082
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 ) we measured
R=18.56+/-0.10 for UT= April 6.06 (182.3 hours after the burst).
Observations were done under bad atmospheric conditions. 

This message may be cited.

Y. Urata(1), T. Miyata(1), S. Nishiura(1), T. Tamagawa(1),
T. Sekiguchi(2), S. Miyasaka(3), C. Yoshizumi(4) 
1; Kiso GRB team
2; National Astromical Observatory of Japan 
3; Tokyo Metropolitan Government
4; Tokushima children's science museum report;

"We have observed the optical afterglow (Peterson and Price GCN1985
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 )
of GRB030329 on the nights of 2003 March 29 and April 1 using the Kiso
observatory (the University of Tokyo) 105 cm Schmidt telescope with B
and R band filters. Our observations started at March 29 13:21:26 (1.8
hour after the burst). 

We have measured the B and R band magnitude using field photometry
(Henden GCN2082
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 ). The results are listed below. 
 The observations and more accurate photometry are in progress.
 
 Date       start time  exp   band  mag     err
 2003-03-29 14:23:50     60.0 R     13.324  0.010
 2003-03-29 15:23:59     60.0 R     12.719  0.010
 2003-03-29 16:21:56    120.0 R     13.754  0.010
 2003-03-29 17:22:20     60.0 R     13.744  0.010
 2003-03-29 17:42:16     60.0 R     13.644  0.010
 2003-04-01 10:56:40    300.0 R     17.281  0.077
 2003-04-01 10:41:15    300.0 B     17.943  0.063

We thank many high school students who participated in the education
program at Kiso observatory in the night to collaborate with us."

This message may be cited.

T. Matheson (CfA), P. Garnavich (Notre Dame), N. Hathi, R. Jansen,
R. Windhorst, L. Echevarria (ASU), J. Lee (Arizona), W. Brown,
N. Caldwell, P. Berlind. M. Calkins and K. Z. Stanek (CfA) report:

We obtained spectra of the afterglow of GRB 030329 (Peterson & Price,
GCN 1985
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 ; Torii: GCN 1986
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 ) with the 6.5-m MMT and Blue-Channel
spectrograph each night from March 30.12 to April 6.15 (UT). The
spectra cover a wavelength range of 350 nm to 850 nm with a resolution
of 0.6 nm (FWHM). The early spectra consist of a power-law continuum
with narrow emission lines originating from HII regions in the host
galaxy (Martini et al. GCN 2013
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 ; Della Ceca et al. GCN 2015
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 ; Greiner
et al. GCN 2020
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 ; Caldwell et al. GCN 2053
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 ).  However, our spectrum
taken Apr. 6.15 (UT) shows a broad peak in flux at approximately 570
nm and another weak deviation from a power-law near 470nm that were
not evident in the earlier spectra.

The April 6 spectrum is well reproduced by adding a spectrum of SN
1998bw (Patat et al. 2001, ApJ, 555, 900) seven days before maximum
light to a power-law distribution. We conclude that a supernova
spectrum is emerging from the afterglow light.  The brightness of the
supernova is approximately V=22 based on the strengths of the broad
features relative to a pure power-law. Further spectroscopy is
planned.

A plot of the spectrum compared with SN 1998bw is available at:
http://cfa-www.harvard.edu/~tmatheson/grb030329_sn.jpg

This message may be cited.

I. Khamitov,  M.Parmaksizoglu (TUG);
I. Bikmaev, N. Sakhibullin, V. Suleymanov (KSU);
Z. Aslan, O.Golbasi (TUG);
R. Burenin, R. Sunyaev, D. Denissenko, M. Pavlinsky,  O. Terekhov, A. 
Tkachenko (IKI); 
U. Kiziloglu, A. Alpar, A. Baykal (METU); 

report:

We continue the monitoring of the GRB 030329 optical afterglow (Peterson
and Price, GCN 1985
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 ) with 1.5-m Russian-Turkish Telescope RTT150
at TUG. 

Starting from 06 Apr 18:33 UT we obtained BVRI (Bessel) images of TO yet, 
12 frames on each band.
Using stars from Henden (GCN 2082
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 ) we measured follow magnitudes:

Time, UT   	R	Rerr
06 Apr. 18:33	18.812	0.056
	18:55	18.716	0.048
	19:16	18.747	0.052
	19:38	18.973	0.063
	20:00	18.956	0.062
	20:21	18.859	0.055
	20:43	18.822	0.051
	21:05	18.921	0.057
	21:26	18.749	0.049
	21:48	18.670	0.046
	22:09	18.713	0.049  

Observational set is continued.

This message may be cited.

D. Bersier, R. Schild and K. Z. Stanek (CfA) report:

We imaged the optical afterglow of GRB 030329 (Peterson & Price: GCN
1985
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 ; Torii: GCN 1986
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 ) with the FLWO 1.2-m telescope between April 5
UT 03:11 and April 6 UT 08:49 using standard BVRI filters. During that
time, the color of the OT seems to have changed by ~0.15 in B-V (OT
getting redder) and by ~0.1 in V-I (OT getting bluer). This seems to
be consistent with the supernova signature discovered by Matheson et
al. (GCN 2107
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 ).

This message may be cited.

A. Henden (USRA/USNO, Flagstaff), B. Canzian (USNO),
A. Zeh, S. Klose (Thueringer Landessternwarte Tautenburg),

on behalf of the FUN and another collaboration

report:


USNO Flagstaff has been observing the optical transient of GRB 030329
starting 0.65 days after the burst with high photometric accuracy. A
plot of the BVRcIc data obtained during the first 8 days after the
burst reveals short-term (during a night) and long-term (over days)
color fluctuations. In particular, the USNO data reveal a broad bump
in the B-Ic color of the  optical transient around day 5 when the
afterglow shows an excess of red light compared to the earlier light
curve. Before the occurrence of this bump the optical transient
reddened continuously but slowly.

Between day 5 and 7 the data reveal also an increase in the B-Rc color
but a decline of the V-Ic and Rc-Ic colors. On day 8, however, this
trend has stopped and the optical transient was considerably redder in
all colors (B-V, V-Rc, Rc-Ic). More precisely, the optical transient
was redder than ever before. Based on the USNO data alone one cannot
decide what the reason for this color evolution is (emission lines
from the underlying host galaxy, a dust echo, broad-band supernova
features, intrinsic afterglow physics, etc.). If it is a supernova
(Matheson et al., GCN 2107
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 ; Bersier et al., GCN 2109
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 ) then the color
changes much more rapidly than predicted by the simplest model (Zeh et
al., GCN 2081
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 ).

E. Semkov (Institute of Astronomy, Sofia, Bulgaria) report:
 
The afterglow of the HETE burst (H2652) GRB 030329 (Peterson & Price, 
GCN 1985
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 ; Torii: GCN 1986
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 ) was observed with the 50/70 cm Schmidt 
telescope of the National Observatory Rozhen (Bulgaria) on 2, 3 and 3 
April, Rc filter, 5 x 300 sec coo-added exposures.
The observations were carried out under good seeing conditions. Using 
field photometry of Henden (GCN2082
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 ) we estimate the brightness of the 
optical afterglow in Rc band as follows.

2.04 (UT 21.3) R=17.66  +/-0.09
3.04 (UT 20.2) R=17.73  +/-0.11
4.04 (UT 19.5) R=18.11  +/-0.18

This message may be cited.

V.Metlov (Crimean Laboratory of the Sternberg Astronomical Institute,
Moscow State University) report:

I have continued photographic observations of the GRB030329 OT found by
B.A.Petrrson and P.A.Price (GCN 1985
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 ) with 50-cn Maksutov telescope at
Crimean Laboratory of the Sternberg Astronomical Institute. Two 80-minute 
exposures have been made on Apr, 4. 
Based on additional filed photometry presented in GCN 2082
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  by A.Henden
I have estimated the OT magnitudes on two new photographs, and also have
made some corrections to my previous (GCN 2102
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 ) estimations. 14 stars
were used to do the calibration.
The results are shown in the table below. The increased uncertainties
of last measurements are caused by affinity to the limiting magnitudes
of our plates (19.0-19.5 in B band, 18.0-18.5 in V band). Despite of it,
it was seen, that began a new fading phase.

   date                 UT           filter      mag     err
2003-04-02      19:33:00-20:33:00       B        18.20   0.15
2003-04-02      20:45:00-21:35:00       V        18.05   0.25
2003-04-04      18:18:00-19:38:00       V       >18.4     -
2003-04-04      19:48:00-21:08:00       B        18.80   0.30

This message may be cited.

V.Lyuty and V.Metlov (Crimean Laboratory of the Sternberg Astronomical
Institute, Moscow State University) report:

We have observed the GRB030329 OT found by B.A.Peterson and P.A.Price
(GCN 1985
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 ) with 60-cm telescope at Crimean laboratory of the Sternberg 
Astronomical Institute. Our observations started at
Mar 31, 18:00 UT. A set of 120 sec. exposures in R (Johnson) filter was
obtained under poor weather conditions.
We have estimated the R magnitudes of the OT using USNO U1050_06350247
star (R=16.06). The results are shown in the table below.

           UT            R
March
        31.7510         17.09
        31.7576         17.04
        31.7604         16.84
        31.7813         16.84
        31.7840         16.94
        31.7868         16.88
        31.7931         17.04
        31.7972         16.90
        31.8056         17.09
        31.8083         16.98
        31.8167         17.12

        Average:        16.98+/-0.03

It is possible that the beginning of the next phase of decrease of OT
brightness took place.

This message may be cited.

A. Zeh, S. Klose (Thueringer Landessternwarte Tautenburg),
A. Henden (USRA/USNO) on behalf of the USNO GRB team and the FUN
   collaboration, and
J. Greiner (MPE Garching),

report:


Stimulated by the recent claim of an appearing supernova (SN) component
(Matheson et al. 2107; Bersier et al., GCN 2109
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 ) we have extended our
numerical model (Zeh et al., GCN 2081
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 ) by the inclusion of a parameter
which describes a delay, dt, between the onset of the SN and the
GRB and have reanalyzed the USNO data on GRB 030329.

The long-term evolution in the B-V, B-Rc, and V-Rc color of the
optical transient (OT) seen in the high-precision USNO data so far can
indeed be fitted very well with dt approximately 1..2 weeks prior to
the burst, although we cannot reproduce the temporary reddening of the
optical transient which was observed on t=8 days after the burst
(Henden et al., GCN 2110
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 ). On day 9 this temporary reddening of the
OT has disappeared. It is well possible that this phenomenon was
related to another episode of flattening of the OTs light curve.

For the sake of clarity we note that the unknown diversity of GRB-SNe
does not allow us to state with certainty that a dt < 0 in our model
does indeed represent a 'SN-first--GRB-later' scenario. So far, this
parameter simply improves the numerical fit if SN 1998bw is used as a
template. Its physical reality remains to be clarified.

J. Suzuki (1), T. Sekiguchi(2), S. Miyasaka(3),
1; Tokyo University of Science
2; National Astronomical Observatory of Japan 
3; Tokyo Metropolitan Government

T. Aoki, Y. Urata, and T. Tamagawa on behalf of the KISO GRB Team report:

"We continue to observing the GRB030329 optical afterglow (Peterson
and Price GCN1985
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 ) using the Kiso observatory (the University of
Tokyo) 105 cm Schmidt telescope with B and R band filters.

We measured the B and R band magnitude using field photometry (Henden
GCN2082
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 ). The results are listed below. The observations and more
accurate photometry are in progress.

           Start  End    exposure  filter mag.   error
2003-04-06 11:13  11:33  300s x 3  R      18.85  0.04
           11:35  11:55  300s x 3  B      19.72  0.05

This message may be cited."

Mike Eracleous (Penn State), Brad Schaefer, and Chris Gerardy
(U. Texas) on behalf of the Hobby-Eberly Telescope GRB followup team
report:

We have obtained several spectra (410-900 nm, resolution 1.6 nm) of
the optical counterpart of GRB030329 (Peterson & Price, GCN 1985
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 ;
Torii: GCN 1986
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 ) with the Hobby-Eberly Telescope and Marcario
Low-Resolution spectrograph. Our spectra of March 31, April 2, and
April 5 (UT) show the following evolution of the spectral properties:
(a) the equivalent widths of the [O III] and H-alpha emission lines is
increasing in a manner consistent with a constant line flux and a
decline of the continuum, and (b) the spectrum of April 5 (UT) shows
evidence of a broad feature underlying the [O III] lines, similar
tresembling that reported by Matheson et al. (GCN 2107
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 ), who interpret
it as due to an emerging SN spectrum. However, the contrast of this
feature in our spectrum is not as high as in the spectrum of Matheson
et al. (taken a day later than ours). As a consequence, we cannot rule
out alternative interpretations, such as the emergence of a host
galaxy spectrum that manifests itself as a break in the power-law
continuum.  Analysis of more recent spectra is under way to clarify
this issue.

Using the [O II] and H-alpha emission line fluxes of Caldwell et
al. (GCN 2053
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 ), we estimate luminosities of 1x10^40 and 4x10^40 erg/s,
respectively (for z=0.168, i.e., a luminosity distance of 880 Mpc),
and infer star formation rates of 0.15 and 0.32 solar masses/yr
(following Kennicutt 1998, ARAA, 36, 189). The upper limit on the host
galaxy from historical images reported by Wood-Vasey et al.  (GCN
1998
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 ; R > 22.28) implies a limit on the absolute magnitude of M_R >
-17.4, which is comparable to that of the LMC. The [OIII]/H-beta ratio
of 2.7 (Caldwell et al.; GCN 2053
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 ) corresponds to an LMC-like faint
starburst galaxy (Ho, et al. 1997, ApJ, 487, 579, Figure 6; Hunter &
Gallagher, 1997, ApJ, 475, 65; Hunter et al. 2001 ApJ, 553, 121),
while the H-alpha luminosity is characteristic of starburst galaxies
(Ho. et al. Figure 2). High-dispersion spectroscopy of these narrow
lines may give more information on the nature of star formation in the
host galaxy.

E. Nishihara, O. Hashimoto, K. Kinugasa (Gunma Astronomical Observatory)

J-, H-, and Ks-band photometry of the optical afterglow (Peterson and
Price GCN 1985
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 , Torii GCN 1986
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 ) of GRB030329 (Vanderspek et al. GCN
1997
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 ) were obtained on the nights of 2003 Apr 29 and 30 at GAO, Gunma,
Japan, using the 1.5-m telescope and the IR Camera.  The observation
started at 13:50 UT (133 min after the GRB trigger).

Our preliminary J-band magnitudes (rough estimate of typical error is
0.1 mag) of the afterglow are given below:

                         ---------------------
                               UT          J
                         ---------------------
                         Apr 29 13.868   11.87
                                15.253   12.42
                                16.902   12.66
                                17.828   12.93
                         Apr 30 12.534   15.10
                                14.159   15.21
                         ---------------------

This message may be cited.

I. Khamitov, M. Parmaksizoglu, K.Uluc (TUG);
I. Bikmaev, N. Sakhibullin, V. Suleymanov, R. Gumerov, A. Ibragimov (KSU);
Z. Aslan, O.Golbasi (TUG);
R. Burenin, R. Sunyaev, D. Denissenko, M. Pavlinsky,  O. Terekhov, A. 
Tkachenko (IKI); 
U. Kiziloglu, A. Alpar, A. Baykal (METU); 

report:

We continue observations of the GRB 030329 optical afterglow (Peterson
and Price, GCN 1985
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 ) with 1.5-m Russian-Turkish Telescope RTT150
at TUG in the Bessel BVRI-bands. 

We obtained 70 exposures at 06 Apr. 18:33UT - 07 Apr. 01:23UT;
and 48 exposures at 07.Apr 17:55UT - 08 Apr. 01:02UT
Second night observations were made under bad weather conditions.
The magnitudes obtained are as follows:

   UT          R      Rerr  		
Apr. 6.79    18.75   0.02
Apr. 6.83    18.76   0.02
Apr. 6.87    18.71   0.02
Apr. 6.92    18.68   0.02
Apr. 6.96    18.70   0.03
Apr. 6.99    18.73   0.02

Apr. 7.74    18.77   0.03
Apr. 7.77    18.78   0.02
Apr. 7.80    18.73   0.03
Apr. 7.80    18.80   0.03
Apr. 7.97    18.91   0.03
Apr. 8.01    18.83   0.03   

There are no significant changes in the fluxes during two 
observational set in all BVRI-bands.

This message may be cited.

T. Matheson (CfA), P. Garnavich (Notre Dame), E. W. Olszewski
(Steward), P. Harding (Case Western), D. Eisenstein (Arizona),
B. Pindor (Princeton), N. Hathi, R. Jansen, R. Windhorst,
L. Echevarria (ASU), J. Lee (Arizona), W. Brown, N. Caldwell,
P. Berlind, M. Calkins and K. Z. Stanek (CfA) report:


Additional spectra of the afterglow of GRB 030329 (Peterson & Price,
GCN 1985
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 ; Torii: GCN 1986
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 ) were obtained with the 6.5-m MMT on
Apr. 8.13 UT. The spectral features discovered by Matheson et al. (GCN
2107
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 ) and confirmed by Garnavich et al. (IUAC 8108) continue to
develop. Subtracting a scaled version of the Apr. 4.27 UT power-law
spectrum from the Apr. 8.13 spectrum reveals an energy distribution
remarkably similar to that of the SN1998bw a week before maximum light
(Patat et al. 2001, ApJ, 555, 900). This spectrum can be seen at

http://cfa-www.harvard.edu/~tmatheson/compgrb.jpg

The spectral similarity to SN 1998bw and other 'hypernovae' such as
1997ef (Iwamoto et al. 2000, ApJ, 534, 660) provides strong evidence
that classical GRBs originate from core-collapse supernovae.

This message may be cited.

S. Covino, G. Ghisellini (INAF, Brera, I); D. Malesani (SISSA, Ts, I);
P.A. Price (Caltech, USA); D. Lazzati, E.M. Rossi (IoA, Cambridge, UK);
G. Chincarini, G. Tagliaferri, F.M. Zerbi (INAF, Brera, I); S. Di
Serego, M. Della Valle, A. Cimatti (INAF, Arcetri, I); F. Fiore, G.L.
Israel, L. Stella (INAF, Roma, I); M. Vietri (Roma 3, Univ, I); N. Kawai
(RICHEN, Japan); G.R. Ricker (MIT, USA); E. Le Floc'h, P. Goldoni, I.F.
Mirabel (CEA, Sacley, F); S. Mereghetti (IASF, Mi, I); E. Costa, P.
Soffitta (IASF, Roma, I); S. Ortolani (Padova Univ., Italy); A. Kaufer,
A. Lopez, P.M. Vreeswijk, P. Vaisanen, A.O. Jaunsen (ESO);

report:

Starting on 2003 April 2.1, we observed the optical counterpart
(Peterson & Price, GCN 1985
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 ; Torii, GCN 1986
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 ) of GRB 030329 (Vanderspek
et al., GCN 1997
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 ). The observations were performed with the ESO VLT-UT1
(Antu) telescope equipped with FORS1, in spectropolarimetric mode.
Several acquisition images were taken, under photometric sky conditions;
here we report the V-band magnitudes of the OT, based on Henden's
calibration (GCN 2023
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 ). Seeing was ~1".


UT         t-t0 (days)  V mag     err
---------------------------------------
Apr 2.089  2.605        17.652 +- 0.015
Apr 2.128  2.644        17.696 +- 0.014
Apr 2.166  2.682        17.738 +- 0.015


The complete analysis of the spectropolarimetric dataset is underway.

We thank the ESO staff at Paranal for their kind and reliable
assistance.

This message may be cited.

A. Henden (USRA/USNO, Flagstaff), B. Canzian (USNO),
A. Zeh, S. Klose (Thueringer Landessternwarte Tautenburg),

on behalf of the FUN and another collaboration

report:


Flagstaff BVRI data reveal that the light curve of the optical
transient (OT) following GRB 030329 has now begun to flatten in all
bands and might be entering the supernova phase. The signal which is
now seen in the light curve shape looks different from all previous
episodes of re-brightening.

The photometric data alone do not yet allow us to state with certainty
what the best fitting parameters of the underlying supernova component
are (see Zeh et al., GCN 2081
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 ). The color evolution of the OT until
day 8 after the burst, which was reported in GCN 2115
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  (Zeh et al.),
seemed to prefer a delay dt between the onset of the supernova and the
onset of the GRB by several days. The inclusion of the Flagstaff data
obtained during the last two nights has changed this picture,
however. Obviously on day 8 the OT underwent another episode of
re-brightening and color change that made it difficult to fit the
observed colors. After exclusion of this effect, a dt close to
0 days is preferred in the color evolution, as well as in the shape of
the R and V-band light curves (-3 < dt <=0). This is in good agreement
with the (stronger) finding based on spectroscopic data (Matheson et
al., GCN 2120
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 ).

Figures will be posted at Jochen Greiners internet GRB page.

A. Simoncelli (INAF, Brera, I), D. Malesani (SISSA, Trieste, I), A.
Della Valle (INAF, Padova, I), N. Masetti (IASF, Bologna, I), L.A.
Antonelli (INAF, Roma, I), S. Covino (INAF, Brera, I), E. Pian (INAF,
Trieste, I), on behalf of a larger Italian collaboration, report

We have obtained BVRI images of the afterglow (Peterson & Price, GCN
1985
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 ) of GRB 030329 (Vanderspek et al., GCN 1997
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 ), using the 182cm
Copernico telescope of the Astronomical Observatory of Padova (Italy),
plus BFOSC. Seeing was ~3"; the afterglow was clearly detected in all
bands; we measured for it the following BVRI magnitudes, with respect to
the calibration performed by Henden (GCN 2082
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 ):


UT start    exptime  filter  mag      err
------------------------------------------
Apr. 4.908   600 s   R       18.14 +- 0.02
Apr. 4.916  1200 s   B       18.88 +- 0.02
Apr. 4.932   600 s   I       17.71 +- 0.02
Apr. 4.941   600 s   V       18.55 +- 0.02


Assuming a powerlaw shape for the spectrum (F_nu propto nu^-beta), the
best fit to our data yields beta~1.

This message can be cited.

G. B. Taylor (NRAO), E. Berger (Caltech), D. A. Frail (NRAO), and
S. R. Kulkarni (Caltech) report:

"Following the detection of the radio afterglow on Mar 30 (Berger
et al. GCN 2014
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 ) from the bright burst GRB 030329 (GCN 1985
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 , 1997
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 )
we observed with the Very Long Baseline Array (VLBA) for
8 hours beginning on April 01.05 UT.  The flux density measured at
8.4 GHz was 8.3 +/- 0.4 mJy.  The source is unresolved by these
observations with a size less than 0.5 mas (size < 1.4 pc given the
redshift of 0.1685 reported by Greiner et al. in GCN 2020
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 ).
Assuming typical parameters for the expansion (e.g. Frail et al. 2000, 
ApJ, 534, 559) we expect a size of about 1.3e17 cm
(0.04 pc) at the time of the VLBA observation (t=2.7 days).
The VLBA position is at ra = 10h44m49.9595s dec = +21d31'17.438"
(equinox J2000) with a conservative error of 0.001 arcsec in each
coordinate.  This position is within 0.02 arcsec of the VLA radio position,
but is 1.21 arcsec from the optical afterglow position
reported by Yamaoka et al. (GCN 1994
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 ) who claim an uncertainty of 0.07
arcsec.  Given that the optical and radio afterglow should be
coincident, we suggest that the optical astrometric position 
suffers from a systematic error.

High frequency VLBI observations are planned with the goal of 
eventually resolving the radio afterglow."

This message may be cited.

A. Henden (USRA/USNO) reports on behalf of the USNO GRB team:

The optical position in the field photometry file (GCN 2023
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 )
   ftp://ftp.nofs.navy.mil/pub/outgoing/aah/grb/grb030329.dat
for the optical transient (GCN 1985
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 ) is given as
    10:44:49.957  +21:31:17.46  J2000
(internal errors of 40mas) using UCAC2 as the reference frame.
This is in good agreement with the recent, more precise,
radio position of
    10:44:49.9595  +21:31:17.438
given by Taylor et al. (GCN 2129
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 ).  The NOFS optical position is
also in disagreement with Yamaoka et al. (GCN 1994
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 ).  Yamaoka et al.
do not give their reference catalog, which might be the
cause for the disagreement.  The position given by
Price and Peterson (GCN 1987
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 ) does not have sufficient precision
in RA to ascertain whether their position matches NOFS and
Taylor et al. within their quoted accuracy.

R. Chornock, R. J. Foley, A. V. Filippenko, M. Papenkova, and D. Weisz,
University of California, Berkeley, report that inspection of CCD
spectra (range 310-1000 nm) of GRB 030329, obtained on Apr. 8 UT with
the Shane 3-m telescope at Lick Observatory, confirms the emergence of
broad bumps (especially at rest-frame 500 nm) characteristic of the
peculiar type-Ic supernovae 1998bw and 2002ap at early times, as announced
by Matheson et al. in GCN 2107
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  and GCN 2120
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 . The association between 
core-collapse supernovae and at least some of the long-duration GRBs thus
seems solid. We expect the supernova features to continue strengthening
with time relative to the power-law continuum of the GRB afterglow.

P.S.  This information also appears in IAUC 8114, but has been reposted
here for the benefit of those GCN subscribers who do not read the
IAU Circulars.

Arnon Dar (Technion) and Alvaro De Rujula (CERN) report:

We use the infamous Cannonball model (CB model) of GRBs
to predict the superluminal motion of the source of the radio 
afterglow (AG) of GRB 030329 (GCN 1985
Loading...
 
 , 1997
Loading...
 
 ), potentially observable 
with the VLBA (see, e.g. GCN 2129
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 ).

The CB model has been succesful in describing GRB 030329 and 
its AG, in predicting the supernova (SN) contribution to the AG, 
and even the date at which the SN was to be convincingly seen [1]. 

In the CB model, the cannonballs responsible for the GRB and the
AG light move superluminally in the sky, as they travel away from
their projenitor SN. THIS MOTION MAY BE OBSERVABLE IN THE 
RADIO AG, IF ITS LOCATION IS FOLLOWED AS A FUNCTION OF TIME [2]. 

The SN cannot be currently seen in the radio, so that it is the 
motion of the radio-AG source (the CB)  that one may try to observe.
In the case of GRB 030329 there were two CBs, one of which dominates
the AG after t ~ 1 day. Using the parameters of this CB determined
in [1] (initial Lorentz factor 1477, viewing angle 2 mrad, and 
deceleration parameter 476 kpc) and Eqs. (30, 31, 41) of [3] we 
obtain the angular distances "alpha" (in mrad) of the dominant CB to 
the SN as a function of "t" (observer's time in days).  For the current 
cosmology (Omega_Lambda=0.7, Omega_Matter=0.3, H_0=75 km/s/Mpc; and for 
z=0.1685, so that the angular distance is 0.64 Gpc) some representative 
results are:

(t, alpha): (0,0); (1,0.22); (2.7,0.49); (5,0.74); (10,1.1); (30,1.9).

This means that from day 2.7 to day 10 the radio source may
have moved 0.6 mrad, and from day 10 to day 30 it may move
an extra 0.8 mrad. Such motion may be observable with the VLBA.

[1] Dado et al. astro-ph/0304106.
[2] Dar and De Rujula, astro-ph/0008474. 
[3] Dado et al. 2003 A&A 401, 243.

Arnon Dar (Technion) and Alvaro De Rujula (CERN) report:

We use the infamous Cannonball model (CB model) of GRBs
to predict the superluminal motion of the source of the radio 
afterglow (AG) of GRB 030329 (GCN 1985
Loading...
 
 , 1997
Loading...
 
 ), potentially observable 
with the VLBA (see, e.g. GCN 2129
Loading...
 
 ).

The CB model has been succesful in describing GRB 030329 and 
its AG, in predicting the supernova (SN) contribution to the AG, 
and even the date at which the SN was to be convincingly seen [1]. 

In the CB model, the cannonballs responsible for the GRB and the
AG light move superluminally in the sky, as they travel away from
their projenitor SN. THIS MOTION MAY BE OBSERVABLE IN THE 
RADIO AG, IF ITS LOCATION IS FOLLOWED AS A FUNCTION OF TIME [2]. 

The SN cannot be currently seen in the radio, so that it is the 
motion of the radio-AG source (the CB)  that one may try to observe.
In the case of GRB 030329 there were two CBs, one of which dominates
the AG after t ~ 1 day. Using the parameters of this CB determined
in [1] (initial Lorentz factor 1477, viewing angle 2 mrad, and 
deceleration parameter 476 kpc) and Eqs. (30, 31, 41) of [3] we 
obtain the angular distances "alpha" (in mas) of the dominant CB to 
the SN as a function of "t" (observer's time in days).  For the current 
cosmology (Omega_Lambda=0.7, Omega_Matter=0.3, H_0=75 km/s/Mpc; and for 
z=0.1685, so that the angular distance is 0.64 Gpc) some representative 
results are:

(t, alpha): (0,0); (1,0.22); (2.7,0.49); (5,0.74); (10,1.1); (30,1.9).

This means that from day 2.7 to day 10 the radio source may
have moved 0.6 mas, and from day 10 to day 30 it may move
an extra 0.8 mas. Such motion may be observable with the VLBA.

* mrad in GCN 2132
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  was corrected to mas 


[1] Dado et al. astro-ph/0304106.
[2] Dar and De Rujula, astro-ph/0008474. 
[3] Dado et al. 2003 A&A 401, 243.

TITLE:   GCN GRB OBSERVATION REPORT
  SUBJECT: GRB 030329: Rc photometry in Loiano
 
  G. Pizzichini and P. Ferrero (IASF/CNR, Bologna), C. Bartolini, A.
  Guarnieri, A. Piccioni (Bologna University), A. Righini (Firenze
  University) and I. Bruni (Bologna Astronomical Observatory) report:
 
  We observed  the optical afterglow (Peterson & Price, GCN
  1985
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 ) of GRB 030329 (Vanderspek et al., GCN 1997
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 ),
  using the 152cm telescope + BFOSC of the Astronomical Observatory in
  Loiano (Italy),
 
  Seeing was  ~ 1.5", but observing conditions were limited, due to
  the low angular distance to the moon and the not perfect weather conditions.
  We co-added the three exposures listed below:
 
   UT start    exptime  filter
  -----------------------------
  Apr. 13.8783  300s     Rc
  Apr. 13.8824  300s     Rc
  Apr. 13.8865  300s     Rc
 
  and used the following stars in Henden's photometric calibration
  (GCN2082
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 ):
 
  RA= 161.174977  DEC= 21.542124
  RA= 161.158874  DEC= 21.562989
  RA= 161.162639  DEC= 21.516308
  RA= 161.166023  DEC= 21.570694
 
  We obtain a preliminary magnitude Rc = 18.66 +/- 0.11.
  This message may be cited.

V. Testa, G. Cocozza, A. Melandri, L.A. Antonelli (INAF-Roma, I), 
D. Malesani (SISSA, Trieste, I), A. Buzzoni, S. Di Tomaso, D. Fugazza,
F. Ghinassi, J.C. Guerra (INAF-TNG), S. Covino (INAF-Merate, I), N. Masetti 
(IASF-CNR, Bologna, I), E. Pian (INAF-Trieste, I) on behalf of a 
larger Italian collaboration, report:
  
"We have obtained VR images of the afterglow (Peterson & Price, GCN
1985
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 ) of GRB 030329 (Vanderspek et al., GCN 1997
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 ), with the Italian 3.6m 
TNG equipped with DOLORES. Observations were performed on Apr. 10,11 and 
14; seeing in the R band was 1.0 arcsec during the first night, 1.2 arcsec 
during the second night, and 1.3 arcsec during the last night. 
The afterglow was detected in both bands with S/N(R,peak) = 43 (first 
night), 37 (second night) and 23 (third night). During the second and 
third nights measurements have been affected by a bright sky background, 
likely due to the moon being relatively close to the target (21 and 24 
degrees respectively).

We measured the following VR magnitudes, with respect to the calibration 
performed by Henden (GCN 2082
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 ):
  
   Obs._date(UT) t_exp(s)  Filt.  Mag    Err(Mag)
   ----------------------------------------------
   10/4 21:38:37  240       V     19.72  0.05
   10/4 21:31:28  240       R     19.34  0.05
  
   11/4 21:35:49  240       V     19.68  0.11
   11/4 22:04:56  240       R     19.45  0.09
  
   14/4 20:33:01  240       V     20.10  0.12
   14/4 20:48:30  240       R     19.71  0.11 
 
All TNG measurements are consistent with a continuosly fading transient. 
 
This message can be cited."

[GCN OPS NOTE (07Nov03): The INAF-TNG author list was changed from
"F. Ghinassi, D. Fugazza, S. Di Tomaso (INAF-TNG)" to
"A. Buzzoni, S. Di Tomaso, D. Fugazza, F. Ghinassi, J.C. Guerra (INAF-TNG)".]

T. Fatkhullin, V. Komarova, V. Sokolov (SAO RAS), V. Kurt (ASC RAS),
A. Cherepashchuk (SAI MSU), K. Postnov (SAI MSU), V. Reshetnikov (AI SPBU),
Alberto J. Castro-Tirado (INTA, Madrid and IAA, Granada)
report:

8 spectra of OT GRB 030329 (Peterson & Prise, GCN 1985
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 ; Torii GCN 1986
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 )
were obtained under the program "Optical identification of gamma-ray burst
sources" (observer A. V. Moiseev, LSPEO SAO RAS)
on the night of 29/30 March 2003 (29.934 - 30.004 UT) with the SAO RAS 6-meter telescope
at the Northern Caucasus,  0.45 - 0.52 days after the detection of
GRB 030329 on Mar. 29.484 UT (G. Ricker et al, IAUC No. 8101).
The observations were carried out with
the integral field spectrograph (Multi Pupil Fiber Spectrograph,
MPFS  http://www.sao.ru/~gafan/devices/mpfs/mpfs_main.htm  )

The 4x2 (sums of 2 consequent) spectra and additional info can be seen at
anonymous FTP-site:
	  ftp://ftp.sao.ru/pub2/grb/GRB030329/

With consideration for z=0.168 the first spectra of the OT GRB 030329
remind the very first spectrum of SN 1987A beginning with lambda=3425A,
(Danziger et al, 1987, A&A, 177, L13; Menzies et al. 1987, MNRAS, 227, 39P)
The same spectral behaiour of OT is confirmed by simultaneous UBVRI
observations with the 1-m (Zeiss-1000) of SAO RAS
starting from March 29.717 to 30.015 (UT).
The data are being processed for more accurate calibration.

A possible interpretation (V.Sokolov):
Perhaps, such a behaviour of the very first spectra of OT GRB 030329,
as well as the case of SN 1987A, could be explained by the fact that the burst
of supernova related to the burst of a compact massive star and
recorded in the very beginning of its GRB evolution was observed
in detail for the second time. The physics of the early SN brightness peak
can be related to the exit of a shock wave (or a jet?) onto the surface
of a compact pre-supernova. (e. g. E. Grassberg, V. Imshennik and
D. Nadyozin, 1971, Astroph. Space Sci., 10, 28). Though the difference
between the types of SN 1987A and SN 2003dh (K. Stanek, T. Matheson,
P. Garnavich et al. astro-ph/0304173), and their pre-supernovae should
be certainly taken into consideration.

We are grateful to our colleagues from the Laboratory of Spectroscopy and
Photometry of Extragalactic Objects for their kind assistance in the
spectral observations with the 6-meter telescope of SAO RAS.

This message may be cited."

K. Lindsay, D. H. Hartmann (Clemson University) 
A. Henden (USNO), A. Zeh, S. Klose (Tautenburg)

Report on behalf of a larger collaboration:

We observed the optical afterglow of GRB 030329,
(=H2656, Vanderspek et al., GCN 1997
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 ), identified
by Peterson & Price (GCN 1985
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 ) and Torii (GCN 1986
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 ). 
Observations were made on Tuesday April 8, 2003 
with the SARA 0.9m telescope at KPNO.  Sixty 300s 
exposures were taken in the B Band.  Observations 
began at 03:07:27 UT and ended at 08:23:12 UT.  All 
observations were carried out under relatively good 
seeing conditions.  Aperture photometry was carried 
out based on the calibration by Henden (GCN 2082
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 ).  

We find an average magnitude of B= 19.8 +/- 0.1.

Comparison with observations carried out at USNO
and our previous observations with SARA indicate
that the afterglow was approximately 0.5 
magnitudes brighter than predicted from previous 
nights. This deviation is consistant with the excess 
light due to the underlying SN (Zeh et al., GCN 2081
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 ).

The SARA observations discussed herein were in part
made possible by generous contributions of telescope
time from Dr. J. Webb, E. Howard, Dr. M. Leake,
M. Williams and Dr. S. Shaw. 

More information on the SARA Observatory can be 
found at http://www.saraobservatory.org/.

This report may be cited.

Y.Efimov, K.Antoniuk, V.Rumyantsev (CrAO) and A.Pozanenko (IKI)   report:

We  have  performed  linear  polarization  observations  of   the optical
counterpart to GRB030329 (Peterson and Price, GCN  1985
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 ; Torii,  GCN   1986
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 )
and   a  reference   star   (RA=161.153362, Decl=+21.449663,  Henden,  GCN
2082
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 )  with 125 cm reflector (AZT-11) equipped with  double  beams  UBVRI
polarimeter. The observations  were done on March 29 between 0.76689 and
0.9230 UT (JD2452728.2669  - 2452728.4230)  at  moderate  sky  condition and
sometimes  variable  transparency.  Also the reference star appears to be an
eclipsing binary (J. Fitzgerald & J. Orosz, GCN 2056
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 , 2070
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 ). However it can
be considered as a  reference star with a sufficient  accuracy because of
both the simultaneous observation of the star by V.Rumyantsev et al. (GCN
2005
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 ) with accuracy better than 0.02mag @ 180 s and orbital period
estimation (GCN  2070
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 ) show that the star was far from eclipsing phase.

The preliminary analysis of UBVRI photometric data shows no significant
color variability of the OT, which is in agreement with the prediction of
color behavior for "standard" afterglow models. More detailed analysis is in
progress.

Polarization measurements were corrected for instrumental effects. The
weighted mean  of  reported  polarization  degree and position angles are
derived from the normalized Stokes parameters. The data obtained for OT and
reference star are presented below. Indicated in the table are: fractions of
Julian Day JD-2452827, filter, polarization parameters (degree P and
position angle PA), their mean errors ME, and the duration DT of
measurements in minutes.

We found that the polarization in R filter may be considered as marginally
detected.  The interstellar polarization in the direction of GRB 030329 is
less then 0.2% according to interstellar polarization data at high  galactic
latitude reported by  Berdyugin et al. (2001,A&A, 372,  276).  The
polarization of the reference star combined from measurements in two nights
(29 and 30 March, 2003) significantly differs from that found for OT of
GRB030329.

Mid time, (GRB 30329) Date: March, 29, 2003
  JD-2452729 FILTER  P (%)  ME    PA    ME   DT

   0.3261    R       0.90   0.39  109   12   86

(Reference star), Combined data March, 29-30, 2003
  FILTER   P      ME     PA      ME      DT

    R      0.33   0.17   174.2   13.7

Detailed polarization analysis in all UBVRI filters is in progress.

T. Fatkhullin, V. Komarova, V. Sokolov (SAO RAS), V. Kurt (ASC RAS),
A. Cherepashchuk (SAI MSU), K. Postnov (SAI MSU), V. Reshetnikov (AI SPBU),
Alberto J. Castro-Tirado (INTA, Madrid and IAA, Granada)
report:

A part of the results of the UBVRcIc observations with the 1-m (Zeiss-1000) of
SAO RAS at two epochs on March, 29 and the next two nights are now presented
at our anonymous FTP-site:
          ftp://ftp.sao.ru/pub2/grb/GRB030329/

One can see the evolution of the early broad-band UBVRI spectra. In
addition, comparison with the MPFS spectra (see GCN #2142
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 ) allows us to 
perform more precise flux calibration of these spectral data.

Sorry! More correct reference quoted in  GCN #2142
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  is E. Grassberg, 
V. Imshennik and D. Nadyozhin, 1971, Astroph. Space Sci., 10, 28

V.Rumyantsev,  E. Sergeeva (CrAO), V.Doroshenko (SAI MSU), 
E.Pavlenko, O.Antoniuk, N.Primak (CrAO), and A.Pozanenko (IKI) report:

We continue to monitor the OT of GRB030329.

Observations were made on April 8, 9, 10, 2003 in  R and I (Johnson)
spectral band with the 70-cm and 38-cm Cassegrain telescopes of CrAO.  Based
on filed photometry by A. Henden (GCN 2023
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 )  we estimate the OT magnitude as
following

Mid time, UT    telescope exposure    mag    err

Apr.08.9284     K-380     20x300s   R 19.35  0.25
Apr.09.9179     AZT-8      8x150s   R 19.56  0.19
Apr.10.8462     AZT-8     10x120s   R 19.80  0.22
Apr.10.8615     AZT-8     10x120s   I 19.32  0.25

This message may be cited.

H. Yamaoka (Kyushu U), T. Kato, M. Uemura and R. Ishioka (Kyoto U)
report: 

  The OT position given in GCN 1994
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  was obtained with respect to the
USN0-A2.0 reference stars (epoch 1955.2).  The large apparent proper
motions of several stars or the systematic displacements were the main
cause of the disagreement noticed by Taylor et al. (GCN 2129
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 ) and Henden
(GCN 2130
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 ).  Taking the same procedure as GCN 1994
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  but using the 2MASS
positions, we obtain a refined position of R.A. = 10:44:49.958 +/- 0.005,
Decl. = +21:31:17.51 +/- 0.07, which is in good agreement with the
radio and optical positions (GCN 2129
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 , 2130
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 ).

This message may be cited.

A. Price (AAVSO); B. Aquino (AWJ); E. Broens (BOS) & J. Hambsch
(HJB) (VVS Werkgroep Veranderlijke Sterren); P. Brown (OPO01 -
Brigham Young University); T. DiLapo (DLN); B. Dillon (DIL) &
J. Dellinger, D. Beaver, P. Garossino, T. Garossino; N.
Dunckel (DNI); T. Durig &  A. L. Seifert, C. B. Norton, G.F. Garland,
J.K. Cole, J.B. Cherry (CLW01 - University of the South); B. Gary
(GBL); B. Granslo (GRL); A. Henden (USRA/USNO); D. Hohman (HDF);
D. Kaiser (KDA); Z. Kereszty (KZX); P. Kilmartin & A. Gilmore (KPM
- University of Canterbury) J. Liesmann (LJI); G. Lubcke (LBG); J.
Mattei (AAVSO); B. Monard (MLF); P. Nelson (NLX); A. Oksanen (OAR)
& P. Tikkanen (TPE); P. P��kk�nen (PPK); D. Starkey (SDB);
A. von der Linden & T. Schrabback (XXX - IAEF, Bonn University);
D. West (WJD) report on behalf of the AAVSO International GRB Network:

   The AAVSO has 444 measurements of of the GRB030329 OT found by
Peterson and Price (GCN 1985
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 ) spanning 03:47 on March 31 to
03:09 on April 17, 2003. All observations have been rereduced using
the final photometry from Henden et al. (GCN 2114
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 )

   A light curve, all data plus a finder chart with the comparison
and check stars used is available at this URL:

         http://www.aavso.org/grb/grb030329.shtml

  Full reports including equipment and site info are available
at ftp://ftp.aavso.org/grb/GRB030329 Many of the FITS images
are available there as well.

 The AAVSO International GRB network is grateful for a generous
grant from the Curry Foundation and to NASA for the financial
support for the High Energy Workshops for Amateur Astronomers.

M.A. Ibrahimov, I.M. Asfandiyarov, B.B. Kahharov (Ulugh Beg Astronomical
Institute of the Uzbek Academy of Sciences), A.Pozanenko (IKI), V.Rumyantsev
(CrAO), G.Beskin (SAO)  on behalf of large collaboration report:

We have observed the OT GRB030329 found by B.Peterson and P.Price (GCN 1985
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 )
using 1.5m telescope of Mt.Maidanak High-altitude Observatory.    Several
BVRI Bessel images were obtained on April, 7,9,10 and 20. The seeing on
Apr.7 was in range of 1-1.5 arcsec, on Apr.10 - 0.9-1 arcsec for R and in
1-1.3 arcsec for B. In Apr. 9 the weather was unfavorable and some images
were obtained trough clouds.  Based on filed photometry still by A. Henden
(GCN 2023
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 ) we estimate the OT magnitudes:

Mid time
UT, Apr. exposure filter mag    err

 7.7819  7x600    B      19.78  0.04
 7.7986  5x600    V      19.20  0.03
 7.7771  8x600    R      18.84  0.03
 7.8160  3x600    I      18.44  0.06
 9.7653  2x600    B      20.07  0.14
 9.7813  2x600    V      19.37  0.08
 9.7729  4x600    R      19.10  0.06
10.7625  6x600    B      19.96  0.08
10.7792  6x600    V      19.56  0.06
10.7354  6x600    R      19.29  0.07
10.7792  4x600    I      19.11  0.08

And  preliminary reduction of measurements on Apr.20 is following

UT, Apr. exposure filter mag

20.6444  2x600    R      19.92
20.6604  2x600    B      21.08

With typical error of 0.15 (B) and 0.13 (R)

Our measurements on Apr. 10 are consistent with TNG observation by V. Testa
et al. (GCN 2141
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 ).   While in Apr. 7 - 10 the brightness of OT  is
consistent with slow fading, we could not detect brightness change in R
(within our accuracy) between observation on Apr.14 (GCN 2141
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 ) and our
measurement on Apr. 20.

A.M.Finkelstein (IPA RAN), A.V.Ipatov(IPA RAN) and Yu.N.Gnedin (Pulkovo
Observatory) report:

GRB 030329 was observed at 3.5 cm with the RTF-32 telescope of the Institute
of Applied Astronomy in Svetloe on 2003 Apr 11 and 12 and at 6 cm with the
RTF-32 telescope of the Institute of Applied Astronomy in Zelenchuk on 2003
Apr 11,12 and 13. The observations in Svetloe have been made in both
polarization modes. The 3.5 cm following flux densities:
2003 Apr 11.18.12  27.1 +/- 7.8 mJy  in the right circular  polarization .
                    7.8 +/- 4.2 mJy  in the left circular polarization .
2003 Apr 11.16.47  30.4 +/- 9.7 mJy  in the right circular polarization.
                   18.7 +/- 4.7 mJy  in the left circular polarization.
2003 Apr 12.18.43  18.1 +/- 5.2 mJy  in the right circular polarization .
                    7.8 +/- 2.8 mJy  in the left circular polarization.
 Over the period of 6-cm observations in Zelenchuk the flux density at April
11 decreased from 179.6 +/- 4.4 mJy at 18.46 UT to 8.3 +/- 3.1 mJy at 22.48
UT. During Apr 12 and 13 the mean flux density was at the level of
approximately 10 mJy.
            This message may be cited.

A.M. Magalh�es, A. Pereyra, T. Dominici and Z. Abraham (IAG, U.
of S�o Paulo) report:

We have obtained R band imaging polarimetry of GRB030329. The
observation was performed with the IAGPOL imaging polarimeter and the
IAG-USP 60cm telescope, at the Laborat�rio Nacional de Astrof�sica site.
The observation spanned the period UT 01:06 to 01:51 on 31 March,
1.519 - 1.592 days after the event, and was made through less than ideal
sky conditions. The double-beam technique provided by a calcite plate
analyser ensured however that useful polarimetric data could still be
obtained.

We have measured the following linear polarization for GRB030329:

P = [1.974 +- 0.477] %, position angle = 83.2 degrees.

(The position angle is already in the equatorial system, increasing from
North to East.)

As a comparison, we have obtained much smaller polarization for field
objects. In particular, for USNO A-2.0 1050-6351075 (object 'A' in
Rumyantsev et al, GCN 2005
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 ) and 1050-6349885, we have obtained the
following linear polarization values: [0.58 +- 0.11] at 66deg and [0.06
+- 0.12] at 21deg, respectively. This low foreground polarization is
consistent with the very low foreground reddening towards the field
(E(B-V)=0.025, Schlegel et al. 1998).

Dilution of the GRB intrinsic polarization by the much fainter (Blake &
Bloom GCN 2011
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 ) host galaxy should be negligible. Polarization within
the host galaxy interstellar medium seems unlikely due to the small
internal extincion (Caldwell et al. GCN 2053
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 ); this should be settled
by variability studies and spectropolarimetry.

We conclude that a substantial fraction of the GRB030329 polarization
is intrisic in nature. This strongly suggests that GRB030329 is
non-spherically symmetric, lending further credence to the asymmetric
fireball scenario (in combination with a physical process that produces
polarization, such as synchtron radiation). The position angle above
should be correlated with the object's beam or jet orientation on the
sky. It would be interesting to see whether a similar position angle
is present in forthcoming resolved radio observations of the source.

This message may be cited.

[GCN OPS NOTE (22Apr03):  The circular was originally submitted
on 14 Apr 03, but was delayed due to email address mismatch.]

GRB 030329: wide-field photograph by R. Tamura 1 hr after the burst

T. Kato (Kyoto U), R. Tamura and T. Inone (Akashi Municipal Planetarium)
report:

   Ryuichi Tamura (Japanese amateur astronomer) incidentally took
wide-field photographs around the afterglow of GRB 030329 one hour
after the burst.  The photographs were taken at two epochs covering
12:28-12:35 UT (starting at 51 min after the burst) and 12:35-12:42 UT.
No obvious optical afterglow was detected on these images.
A quick look of the first image has yielded an upper limit of
about 8.5 mag.  Further analysis of the images is in progress.

   The enlarged image around the GRB is placed at:

   http://www.kusastro.kyoto-u.ac.jp/vsnet/GRB/tamura1.gif

This message may be cited.

S. Covino, G. Ghisellini (INAF, Brera, I); D. Malesani (SISSA, Ts, I); 
P.A. Price (RSAA, ANU); D. Lazzati, E.M. Rossi (IoA, Cambridge, UK); G. 
Chincarini, G. Tagliaferri, F.M. Zerbi (INAF, Brera, I); A. Cimatti, S. Di 
Serego, M. Della Valle (INAF, Arcetri, I); F. Fiore, G.L. Israel, L. 
Stella (INAF, Roma, I); M. Vietri (Scuola Norm. Sup., Pisa, I); N. Kawai 
(Tokyo Tech, Japan); G.R. Ricker (MIT, USA); P. Goldoni, E. Le Floc'h, 
I.F. Mirabel (CEA, Sacley, F); S. Mereghetti (IASF, Mi, I); E. Costa, P. 
Soffitta (IASF, Roma, I); S. Ortolani (Padova Univ., I); A.O. Jaunsen, A. 
Kaufer, A. Lopez, P. Vaisanen, P.M. Vreeswijk (ESO);

report:


Starting on 2003 April 2.1 (3.6 days after the GRB), we observed the 
optical counterpart (Peterson & Price, GCN 1985
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 ; Torii, GCN 1986
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 ) of GRB 
030329 (Vanderspek et al., GCN 1997
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 ). The observations were performed with 
the ESO VLT-UT1 (Antu) telescope equipped with FORS1, in 
spectropolarimetric mode. At that time, the afterglow had a magnitude V ~ 
17.7 (Covino et al., GCN 2122
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 ).

Our spectrum spans the wavelenght range 350-850 nm. Several narrow 
emission lines are clearly detected (e.g. Greiner et al., GCN 2020
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 ).

The polarization level is found very small, yet significantly nonzero, 
decreasing from (0.9+/-0.1)% in the blue to (0.5+/-0.1)% in the red part 
of the spectrum (1-sigma errors); the polarization angle also shows a 
mildly significant variation from (83+/-4) deg in the blue to (73+/-5) deg 
in the red. These trends are consistent with the effect of a mildly 
polarizing Galactic/host ISM on a intrinsically polarized afterglow.

In particular, the values we obtain in correspondence of the R-band 
(lambda ~ 650 nm) are P = (0.5+/-0.1)% and theta = (73+/-5) deg. 
Comparison of our result with previous measurements (Efimov et al., GCN 
2144
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 ; Magalh�es et al., GCN 2163
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 ) might indicate some time variability on 
a few-days timescale.


We thank the ESO staff at Paranal for their kind and reliable assistance.

This message may be cited.

D. Zaritsky (U. Arizona), M. Bolte (UCSC), P. M. Garnavich (Notre
Dame), A. Z. Bonanos and K. Z. Stanek (CfA) report:

Spectra of the optical afterglow of GRB 030329 (Peterson & Price, GCN
1985
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 ; Torii: GCN 1986
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 ) and supernova 2003dh (Garnavich et al.  IAUC
8114) were obtained with the 6.5-m MMT on April 24.15 (UT) and with
the Keck-II telescope and ESI spectrograph on April 24.36. Preliminary
analysis of the spectra show broad peaks at 560 nm, 450 nm and a sharp
break in the continuum at 390 nm (all in the rest frame).

The spectrum continues to closely follow the development of SN~1998bw
(Patat et al. 2001, ApJ, 555, 900). The feature at 450 nm was not
present on spectra of SN 2003dh taken April 6 (Matheson et al. GCN
2107
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 ) and suggests a significantly lower photospheric velocity in the
current spectrum. SN 1998bw developed the 450 nm feature around
maximum light and this implies SN 2003dh is now at or past its
maximum.

The continuum of SN 2003dh is bluer than SN 1998bw at a similar phase,
which suggests that the afterglow light still contributes to the total
flux.

The April 24 MMT spectrum is available at:

http://www.nd.edu/~pgarnavi/grb030329_apr24.jpg

This message may be cited.

A.V. Sergeev ( IC AMER observatory, Terskol), 
V.V. Golovnya, T.P. Sergeeva, L.K. Pakuliak, L.N. Kizyun, S.V. Shatohina.
(Main Astronomical Observatory, Kiev)

We have undertaken the  review of the sky area  of GRB 030329 (Peterson
& Price, GCN 1985
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 ) on astronegatives, collected in Ukrainian NAS Main
astronomical observatory plate archive (1950-1998). All the plates,
covered the area with  GRB 030329, were taken for an analysis.   The
comprehensive investigation  of these images shows nothing at this
location.

The most reportable results are given in the table:

      Y  M D.UT        UT       M     T     N   Prg Dim,cm

1   19820324.853230  20:28:39  15.2  DWA    34  FON 30x30
2   19820324.853230  20:28:39  15.2  DWA    35  FON 30x30

3   19900228.938966  22:32:07  14.6  DWA  1613  FON 30x30

4   19910411.813130  19:30:54  15.0  DWA  1772  FON 30x30

5   19920228.926992  22:14:52  14.6  DWA  1968  FON 30x30

6   19810226.866267  20:47:25  13.1  DWA  1893   MP 30x30
    19810226.873539  20:57:54  13.1  DWA  1893   MP 30x30
    19810226.879171  21:06:00  13.1  DWA  1893   MP 30x30

7   19810226.879171  21:06:00  13.2  DWA  1894   MP 30x30
    19810226.879171  20:47:25  13.2  DWA  1894   MP 30x30
    19810226.879171  20:57:54  13.2  DWA  1894   MP 30x30          

8   19860404.842854  20:13:43  13.6  DWA  2879   MP 30x30
    19860404.848484  20:21:49  13.6  DWA  2879   MP 30x30
    19860404.853217  20:28:38  13.6  DWA  2879   MP 30x30

9   19860404.842915  20:13:48  13.8  DWA  2880   MP 30x30  
    19860404.845126  20:16:59  13.8  DWA  2880   MP 30x30  
    19860404.845183  20:17:04  13.8  DWA  2880   MP 30x30  

10  19860408.845126  20:16:59  13.2  DWA  2883   MP 30x30
    19860408.847777  20:20:48  13.2  DWA  2883   MP 30x30
    19860408.850548  20:24:47  13.2  DWA  2883   MP 30x30

11  19860408.845183  20:17:04  13.2  DWA  2884   MP 30x30
    19860408.847835  20:20:53  13.2  DWA  2884   MP 30x30
    19860408.850605  20:24:52  13.2  DWA  2884   MP 30x30

12  19820326.833255  19:59:53  13.5  DWA  2324 AREA 30x30
    19820326.847106  20:19:50  13.5  DWA  2324 AREA 30x30

13  19820326.833255  19:59:53  13.6  DWA  2325 AREA 30x30
    19820326.847106  20:19:50  13.6  DWA  2325 AREA 30x30


M 	- limited mag.
T 	- telescope;
N 	- plate number;
Prg  	- Observational Project;
DWA 	- Double Wideangle Astrograph (D/F=40/2000, M=103"/mm)
	  of the Ukrainian NAS Main astronomical observatory in Kiev
          (Marsden's number - 83);
FON 	- Project Photographic Review of Northern Sky [3];
AREA 	- Projects of Special Programm of Photographic Review in areas
	  with special sky objects [1,2];

References:
 1. L.Pakulyak , N.Kharchenko,  E.Izhakevich, V.Golovnya, V.Kisljuk,
V.Andruk. Data base of photographic observations of celestial bodies of
Golosiiv   observatory. Baltic Astron.   6, 1997.
 2. L.Pakulyak,  N.Kharchenko,  E.Izhakevich, V.Golovnya,  V.Andruk,
V.Kisljuk. Data base of photographic observations of celestial   bodies
of Golosiiv   observatory in Kiev. Newsletters of   IAU WG "Wide-field
imaging"  No 9, 1997
3. V.Kislyuk, A.Yatsenko, G.Ivanov, L.Pakuliak, T.Sergeeva.  The
FON Astrographic  catalogue (FONAC): version1.0.  Proc. of Journees
1999 and IX     Lohrmann-Kolloquium  "Motion of celestial   bodies,
astromerty and astronomical reference frames", Drezden, September
13-15,1999

 This message may be cited.

-----------------------------------------------------------------------------
 Centre  Astronomical and Medico-Ecological Researches of Academy of Sci.
         Observatory at peak Terskol, Russia.  Phone (866-39)-71406   
-----------------------------------------------------------------------------

S. Zharikov, G. Tovmassian, M. Richer (OAN SPM IA UNAM, Ensenada, Mexico)
report:

We have observed the OT GRB030329 found by B.Peterson and P.Price (GCN 
1985
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 ) using 1.5m telescope of OAN-SPM Observatory, BC, Mexico. 
A set of exposures in UBVRI Bessel filters was obtained 
24 April and 25 April under photometric and good seeing conditions. 
Standard stars RU 149  from Landolt's  catalogue
were used for photometric calibrations in the each night.

The results of photometry of summed images are following:
24 April
<Tobs>      Texp.   Filter  Mag.

UT 5:50    5400sec   U    21.76(12)
UT 6:56    4800sec   B    21.51(6)
UT 5:54    2400sec   V    20.73(4)
UT 6:30    3300sec   R    20.17(5)
UT 6:10    2400sec   I    19.90(5)
Corresponding color indexes are
 
U-B = 0.25(14) B-V = 0.78(7)
V-R = 0.56(6)  R-I = 0.27(6) 


25 April   
<Tobs>      Texp    Filter   Mag.
UT 5:10   5400sec   B      21.63(5) 
UT 7:30   3600sec   V      21.72(4)
UT 6:17   2400sec   R      20.16(5)
UT 8:00   3600sec   I      20.01(5)

The magnitudes no changed during those nights.
The OT source looks like a point-like object.
Two faint extended objects detected nearly OT position.
O1: 10:44:50.03 J2000  +21:31:10  R~22.5  distance from OT is about 7"
O2: 10:44:49.4  J2000  +21:31:14  R~22.9  distance from OT is about 9"

This message may be cited

S. Zharikov reports:

I had a type in GNC2171.
The V magnitude at 25 April UT 7:30 GNC2171 is 20.72(4).
 
Thanks Dr. Arnon Dar and Dr. Daniele Malesani for note it.

P.W. Schnoor, D.L. Welch, G.J. Fishman and A. Price report, on behalf 
of the AAVSO GRB-SID Network, on the detection of GRB030329 as a sudden 
ionospheric disturbance (SID), observed by Peter Schnoor of Kiel, Germany.

A disturbance of the Earth's ionosphere was observed coincident with the
HETE detection of GRB030329. This SID was seen as an increase in the signal
strength from a Low Frequency (LF) radio beacon received in Kiel, transmitted 
as a time signal from station HBG (75 kHz) near Geneva, 920 km from the 
receiver. (Note: This is not a radio detection of GRB030329; this
disturbance was caused by the prompt X-rays and/or gamma-rays from GRB030329
ionizing the upper atmosphere and  modifying the radio propagation properties 
of the Earth's ionosphere.) Due to the sub-burst longitude and latitude and 
the geographical distribution of LF/VLF beacons and monitoring stations, this 
was the only recording (positive or negative) where GRB030329 illuminated the 
ionosphere along a signal path.

Several plots of the SID detection, including one with an overlay of 
the HETE X-Ray lightcurve are available at the URL
          http://www.qsl.net/df3lp/projects/sid/index.html
Additional details of the observation are also available at this site.

While this type of observation is not yet quantitative, future observations
of enough GRBs may allow a quantitative measurement to be made of the prompt, 
total ionizing flux (X-rays and gamma-rays) incident at the Earth over an 
extremely broad energy range. This measurement is not now attainable with any 
single spacecraft and will not be, until the launch of the NASA GLAST mission 
in 2006. 

Previously, at least three other transient, high-energy sources have 
produced detectable ionospheric disturbances, as measured with VLF
receivers: GRB830801 (Fishman and Inan, Nature v.331, p.418, 1988); XRF
020427 (GCN 1394
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 ), and the Aug. 27, 1998 super-flare from SGR 1900+14 (Inan,
et al., Geophys. Res. Lett., v.26, p.3357, 1999).

The AAVSO SID-GRB network is a worldwide network of observers monitoring 
VLF and LF beacons for SIDs of non-solar origin. The AAVSO Solar Committee 
has been monitoring and reporting solar-induced SIDs since the 1950's. This 
group intends to continue and expand this monitoring network.

This message may be cited.

E. Semkov (Institute of Astronomy, Sofia, Bulgaria) report:
 
We continue our observations of the afterglow of HETE burst (H2652) GRB 
030329 (Peterson & Price, GCN 1985
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 ; Torii: GCN 1986
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 ) with the 2m RCC 
telescope of the National Astronomical Observatory Rozhen (Bulgaria).
We obtained four 300 s exposures on 25 Apr UT 19:30 with Photometrics 
CCD camera and Rc filter. The observations were carried out under good 
seeing and atmospheric conditions. Using field photometry of Henden 
(GCN2082
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 ) and after co-adding of frames we estimate the brightness of 
the optical afterglow as Rc = 20.21 +/-0.09.

This message may be cited.

M.A. Ibrahimov, I.M. Asfandiyarov, B.B. Kahharov (UBAI), A.Pozanenko (IKI),
V.Rumyantsev (CrAO), G.Beskin (SAO)  on behalf of large collaboration
report:

We have observed the OT GRB030329 found by B.Peterson and P.Price (GCN 1985
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 )
���� 1.5m telescope of Mt.Maidanak High-altitude Observatory  (UBAI).
Several BVRI Bessel images were obtained on April  20, 25 and 27. The seeing
on Apr.25 was in range of 1-1.5 arcsec, and on Apr.27 is less than 1 arcsec
for all filters.  Based on filed photometry  by A. Henden (GCN 2082
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 ) we
estimate the OT magnitudes:

Mid time  exposure filter mag    err
UT, Apr.  sec

20.664   1200     B     21.09  0.10
20.648   1200     R     19.91  0.06

25.745   2400     B     21.83  0.10
25.776   1800     V     20.76  0.08
25.723   1800     R     20.13  0.05
25.799   1800     I     20.01  0.11

27.731   2100     B     21.62  0.12
27.731   1500     V     20.94  0.11
27.731   2400     R     20.24  0.05
27.731   1500     I     19.70  0.10

This message may be cited.

L. Kindt, H. H. Andersen and A. Jakobsen (University of Copenhagen) report:

We have obtained V, R and I-band images of the error box of GRB 030329 
(Peterson & Price 2003, GCN 1985
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 ) using the Danish 0.4-m Brorfelde Schmidt 
telescope. We compared our images with the Digitized Sky Survey and detected
the optical afterglow of GRB 030329 at:

RA: 10:44:50.03   Dec: +21:31:18.1   +- 0.5 arcsec     (J2000)

The following table contains our data for this object:


Date	Time(UT)   Exposure time(s)	Band	Magnitude   
--------------------------------------------------------------
Mar 29   20:21 	   	1080 		R	14.54+-0.01		
Mar 29   20:58 	    	 600 		R	14.57+-0.01		
Mar 30   19:16 	    	 360 		R	16.35+-0.05		
Mar 30   19:30 	    	 540 		R	16.35+-0.04		
Mar 31   21:18	    	 540 		R	16.80+-0.04	
Apr 7    21:00 	    	 270 		R	19.24+-0.29		
Apr 7    21:08 	    	 540 		R	19.20+-0.18		
Apr 7    21:45 	   	1620 		R	18.92+-0.13		
Apr 7    22:26	   	1800 		I	18.82+-0.14		
Apr 7    23:06	   	1800 		V	19.09+-0.14		
--------------------------------------------------------------
Time is measured from start of observation.

The photometry of the afterglow is with respect to 11 stars from 
Henden (GCN 2023
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 ). The quoted errors in the I and V bands may be 
underestimated. We fitted a single power law to our data in the 
R-band. We found a power law slope of 1.31 +- 0.04.

The combined images are made available at:
http://www.fys.ku.dk/~kindt/bachelor/

Thanks to J. Hjorth, K. Augustesen, and H. Pedersen.

I. Khamitov (TUG), I.Bikmaev (KSU), M.Parmaksizoglu (TUG);
N. Sakhibullin, V. Suleymanov (KSU);
R. Burenin, R. Sunyaev, D. Denissenko, M. Pavlinsky, O. Terekhov, A.
Tkachenko, M.Gilfanov (IKI);
Z. Aslan, O.Golbasi (TUG);
U. Kiziloglu, A. Alpar, A. Baykal (METU);

report:

We continue observations of the GRB 030329 optical afterglow (Peterson
and Price, GCN 1985
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 ) with the 1.5-m Russian-Turkish Telescope RTT150
at TUG.

A set of 18 exposures by 5 min. duration each  with Rc Bessell filter has 
been obtained on the night May 02/03, 2003, under good photometric 
conditions and average seeing of 1.3 arcsec.  A new TE Andor CCD with 
Marcony back-illuminated 2048 x 2048 chip was used as the detector with 
the working chip temperature -60 C. We grouped exposures by 3 frames and
results of Rc photometry relative to the stars from Henden (GCN 2082
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 )
are given in the Table below. We integrated all exposures and made PSF
subtraction from the OT's star-like structure to find the presence of
the host galaxy. No object brighter than R ~ 23.5 mag was found at the
position of the afterglow. A faint extended detail is seen at 1 arcsec
west side of OT position on the residual image at the brightness level 
of limiting magnitude. The limiting magnitude is defined by fringe
structures.

We  confirm the presence of two bright enough sources O1 and O2
at the 7 and 9 arcsec distances from OT indicated by S.Zharikov et al
(GCN 2171
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 ) and estimated their magnitudes as R = 22.1 and 22.4
correspondingly.

Table of Rc photometry
  UT        R    Rerr
May 2.774 20.51 0.07
May 2.786 20.65 0.07
May 2.800 20.34 0.06
May 2.813 20.62 0.08
May 2.826 20.63 0.07
May 2.838 20.61 0.07

This message may be cited.

GRB 030329: all-sky CCD images by K. Shiokawa immediately after the burst

T. Ishida (Nishi-Harima Astronomical Observatory), T. Kato (Kyoto U)
and K. Shiokawa (Nagoya U) report:

   K. Shiokawa (Nagoya U) is taking all-sky CCD images at 572.5nm for
monitoring night sky light.  As a preliminary inspection, we have examined
four images immediately after the GRB 030329 burst time,
whose exposures started at 11:27, 11:57, 12:27 and 12:57 UT, respectively.
All images are taken every 30 minutes with 105 seconds exposure.

No obvious optical afterglow was detected on these images.  
A quick look of each image has yielded an upper limit of about 6.4 mag.  

Observation system used are described in 
Shiokawa, K. et al. 1999, Earth, Planets, and Space, 51, 887-896, and
Shiokawa, K. et al. 2000, Adv. Space Res., 26, 1025-1028.

Further analysis of the images is in progress.

This message may be cited.

I. Khamitov (TUG), I.Bikmaev (KSU), M.Parmaksizoglu (TUG);
N. Sakhibullin, V. Suleymanov (KSU);
R. Burenin, R. Sunyaev, D. Denissenko, M. Pavlinsky, O. Terekhov, A.
Tkachenko, M.Gilfanov (IKI);
Z. Aslan, O.Golbasi (TUG);
U. Kiziloglu, A. Alpar, A. Baykal (METU);

	The combined 90 min image of the GRB 030329 optical afterglow 
(Petersonand Price, GCN 1985
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 ) obtained with the 1.5-m Russian-Turkish Telescope 
RTT150 at TUG in Bessell Rc filter on the night May 02/03, 2003, can be found in 
http://www.tug.tubitak.gov.tr/gozlemler/grb030329/grb030329.html

	On the web-site we present images of TO field befor and after 
PSF-model substraction. The PSF substracted image was used for the estimation of 
upper limit of host galaxy (Khamitov at. al, GCN 2198
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 ).

This message may be cited.

GRB 030329: High-Resolution Spectroscopy of the Host

J. S. Bloom (CfA/Harvard), N. Morrell (Las Campanas Observatory),
S. Mohanty (CfA) report:

"Beginning May 7.01 UT, we observed the position of the optical
transient (Peterson & Price, GCN 1985
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 ) of GRB 030329 (Vanderspek et
al., GCN #1997
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 ) using the Magellan Inamori Kyocera Echelle (MIKE)
Camera on the Baade 6.5 m at the Las Campanas Observatory.  The
dispersion at 7600 Angstrom (Ang) is 0.053 Ang/pixel. The narrow
emission lines (Martini et al., GCN #2013
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 ; Della Ceca et al., GCN
#2015
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 ; Greiner et al. #2020; Caldwell et al., GCN #2053
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 ; Eracleous et
al., GCN #2117
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 ), presumably from the host galaxy, are well detected in
each 1800 sec exposure.  Using a fit to the H-alpha line, we find the
heliocentric systemic redshift of the host galaxy is:

         z = 0.168541 +/- 0.000004

(statistical error). This is most precise emission line redshift of a
GRB host galaxy reported to date. This redshift is consistent with the
host redshift reported previously (Greiner et al., GCN #2020
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 ;
Eracleous et al., GCN #2117
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 ; Caldwell et al., GCN #2053
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 ).

The emission lines are resolved in the dispersion direction with a
FWHM (H-alpha) of 1.44 +/- 0.02 Ang (56.1 km/s). While the core of the
emission lines can be fit by a Gaussian, extended wings of emission
and similar velocity substructure within the profiles are apparent. In
particular, we identify a faint emission structure that is ~66 km/s to
the red of the central core. The host plus OT continuum is discernible
in each echelle order redward of ~7000 Ang.

In ~0.4 arcsecond seeing the emission from the host plus OT is still
unresolved in the spatial direction. The compactness, the relatively
low mass implied by the velocity structure of the emission lines, and
the faintness of the host (Blake & Bloom; GCN #2011
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 ) all continue to
support the notion of the host of GRB 030329 as an intrinsically
underluminous galaxy (Eracleous et al., GCN #2117
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 ). Despite the low
overall star formation rate of the host (Caldwell et al., GCN #2053
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 ),
given the high equivalent widths of the detected lines, the
star-formation rate per unit mass may be appreciable."


This message may be cited.

K. Sasaki (Japan Fireball Network), M. Tomita (Japan Fireball
Network), K. Ohnishi (Nagano National College of Technology), 
and K. Torii (RIKEN) report:

 The sky area of GRB 030329 (Vanderspek, et al., GCN 1997
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 ) was
contemporaneously photographed on 2003 March 29 by K. Sasaki and
M. Tomita with all-sky patrol cameras.

 In the frames tabulated below, no significant object is found at the
position of the optical afterglow (Peterson and Price, GCN 1985
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 ;
Torii, GCN 1986
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 ). We derive preliminary upper limits for the optical
transient by comparison with either 41 LMi (V=5.1) or 54 Leo (V=4.3)
which is significantly detected.

Data from KS
-----------------------------
Start(UT) End(UT) Mag.
-----------------------------
10:40:00 10:59:58 >5.1
11:00:00 11:19:58 >5.1
11:20:00 11:39:58 >5.1
11:40:00 11:59:58 >5.1
-----------------------------

Data from MT
-----------------------------
Start(UT) End(UT) Mag.
-----------------------------
10:30:00 10:59:00 >4.3
11:00:00 11:29:00 >4.3
11:30:00 11:59:00 >4.3
12:00:00 12:29:00 >4.3
12:30:00 12:59:00 >4.3
-----------------------------

 Effective exposure for each frame,
399 s for KS and 580 s for MT, is 1/3 of the elapsed time
due to a rotating shutter in front of the optics.

 Details of the instruments, originally designed for detecting
fireballs (bright meteors), are as follows.

Position of the observatory: KS
Iwate, Japan
141d08m24s E, +39d28m22s N, 100m altitude

Position of the observatory: MT
Ishikawa, Japan
136d48m01s E, +36d55m39s N, 10m altitude

The following instruments are common to the two observatories.

Camera: Canon T70 with command back
Optics: Canon New FD 15mm f/2.8 full-frame fish-eye lens, used at f/2.8
Filter: No
Film: Kodak TMAX 400
Rotating shutter: Open fraction is 1/3
---------------------------------------------

M.A. Ibrahimov, I.M. Asfandiyarov, B.B. Kahharov (UBAI), A.Pozanenko (IKI),
V.Rumyantsev (CrAO), G.Beskin (SAO)  on behalf of large collaboration
report:

We have observed the OT GRB030329 found by B.Peterson and P.Price (GCN 1985
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 )
with 1.5m telescope of Mt.Maidanak High-altitude Observatory  (UBAI).
Several BVRI Bessel images were obtained on May 3, and 5 under good
photometric and seeing conditions  (1-1.5 arcsec).   Based on filed
photometry  by A. Henden (GCN 2082
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 ) we estimate the OT magnitudes:

Mid time  exposure filter mag      err
UT, May.  sec

03.700    2400     B      22.14    0.13
03.726    1800     V      21.29    0.10
03.670    1800     R      20.87    0.09
03.750    1800     I      20.08    0.12

05.690    3000     B      22.08    0.11
05.722    1800     V      21.33    0.08
05.655    1800     R      20.74    0.10
05.746    1800     I      20.28    0.15

Multicolor observations will be continued.

I.Bikmaev (KSU), I. Khamitov (TUG);
N. Sakhibullin, V. Suleymanov (KSU);
R. Burenin, R. Sunyaev, D. Denissenko, M. Pavlinsky, O. Terekhov, A.
Tkachenko, M.Gilfanov (IKI);
Z. Aslan, O.Golbasi (TUG);
U. Kiziloglu, A. Alpar, A. Baykal (METU);
�
report:
�
We continue observations of the GRB 030329 optical afterglow (Peterson
and Price, GCN 1985
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 ) with the 1.5-m Russian-Turkish Telescope RTT150
at TUG.� During the nights of May 3,4,7, 2003,� series of� 5 and 15 min
exposures with V-filter have been obtained under good photometric
conditions and average seeing of 1.3 arcsec.� ANDOR TE 2048 x 2048 CCD has
been used as the detector.
�
Results of OT�our photometry (based on Henden's list, GCN 2082
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  ), averaged
over for each�night,�are�as follow:
�
� Midtime� Vmag�� Verr Total Exp. sec
�
� 03.86UT� 21.40� 0.07 10200
� 04.86UT� 21.33� 0.07 11400
� 07.86UT� 21.60� 0.08��9300
�

Additional note:
Probably, a moved object was found in the vicinity of the OT. This object
was labeled as "O2" in Zharikov et al. (GCN 2171
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 ) and as "A" in� Blake and
Bloom (GCN 2011
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 ).
�
We integrated all the three night� observations into�one image and�
estimated the magnitudes of the sources� in the afterglow vicinity as
��������������
        V����� Verr
�
O1 (B) 23.0�� 0.2
O2 (A) 22.6�� 0.1
�
Using the coordinates of the reference stars�� from Henden's list� we have
determined the positions of OT� and O1, O2 as
�
     RA(2000.0) DEC(2000.0)
�
OT 10:44:49.958 21:31:17.50
O1 10:44:50.039 21:31:10.86
O2 10:44:49.373 21:31:15.02
�
The comparision of coordinates with those given by Blake and Bloom has
shown that position of the source "A" is different by 6 arcsec while� the�
the�position of the source "B" is in agreement �within� 0.5 arcsec 
positional error of Blake and Bloom.
�
We estimate the color of O2 as� V-R = 0.2,� and of O1 as V-R = 0.9
(R mag estimates are taken from Khamitov et al., GCN 2198
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 )
�
Taking into account the�apparent magnitudes, color and considerable 
positional shift, we suppose that this is�an object nearer to the Sun. 
Additional observations are encouraged.�
�
This message may be cited.

Y. Okamoto (NIFTY-Serve Space Forum), K. Ohnishi (Nagano National
College of Technology), and K. Torii (RIKEN) report:

 The sky area of the GRB 030329 (Vanderspek, et al., GCN 1997
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 ) was
contemporaneously imaged with the Yatsugatake Camera between 2003
March 29 10:00 UT (97 minutes before burst) and 14:00 UT. The
Yatsugatake Camera is an ultra wide field (85 x 70 deg) video camera
(focal length 3.5mm, f/1.4 lens equipped with Sony XC-75) placed at an
altitude of 1000m in Yatsugatake, Japan. Images are output in NTSC
format after 8-s (on-chip) integrations, stored to frame memory (MSJ
SS-10), and recorded to timelapse video tape. The camera has built-in
infrared-cut filter while no additional filter is used.

 By now, we have digitized and inspected the data between 10 minutes
before and after the burst and created running mean images of four
consecutive frames. In these images, a neighboring V=5.1 star (41 LMi)
is clearly detected while no transient stellar object brighter than 41
LMi is seen at the position of the optical afterglow (Peterson and
Price, GCN 1985
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 ; Torii, GCN 1986
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 ). We therefore derive preliminary
upper limit of 5.1 mag for an optical transient associated with this
GRB on continuous 32-s time bins between 2003 March 29 11:27 UT and
11:47 UT. Further analysis is in progress.

G. Pizzichini and P. Ferrero (IASF/CNR, Bologna), C. Bartolini, 
A. Guarnieri, A. Piccioni (Bologna University), A. Righini (Firenze 
University) and I. Bruni (Bologna Astronomical Observatory) report: 
 
The Rc magnitude quoted by us for the OT of GRB030329 in GCN 2136
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was not correct, due to a bad subtraction of the background
in conditions of nearly full moon.
By coadding the three exposures listed below:   
-- 
   UT  start    exptime  filter
  -----------------------------
  Apr. 13.8783  300s     Rc
  Apr. 13.8824  300s     Rc
  Apr. 13.8865  300s     Rc

and using the star at RA = 161.231899, DEC = 21.522793,
in the new field photometry given by Henden, GCN 2082
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 , 
we now find Rc = 19.53 +- 0.20 .
 
In the following night, by coadding the exposures:

-
   UT  start    exptime  filter
  -----------------------------
  Apr. 14.8879  300s     Rc
  Apr. 14.8923  300s     Rc
  Apr. 14.8973  300s     Rc

 and still under very unfavorable conditions because of the moon,
we find Rc = 20.27 +- 0.33. Errors quoted are 1 sigma.
  
We thank Dr. A. Henden for promptly signalling the problem to us and
Dr. E. Palazzi for useful advice.

A.Tiengo (IASF-Milano),  S.Mereghetti (IASF-Milano), and N.Schartel
(XMM-Newton SOC, Villafranca) report:

An XMM-Newton TOO observation of GRB030329 (Ricker et al. IAU Circ. 8101)
has been performed on May 5, 2003 from 12:30 to 24 UT.

A source positionally consistent with the optical transient of GRB030329
(Price and Peterson, GCN 1987
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 ) has been detected with the EPIC MOS and PN
cameras.  Its spectrum can be fit by a power law with photon index
2.0+/-0.25 and absorption smaller than 6x10^20 cm^-2.

The 2-10 keV observed flux is (2.1+/-0.6)x10^-14 erg cm^-2 s^-1.

Comparison with previous X-ray observations obtained with RXTE (Marshall
and Swank, GCN 1996
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 ; Marshall et al., GCN 2052
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 ) indicates that the X-ray
flux decay is consistent with a power law F ~ t^(-1.7).

J. Gorosabel (IAA-CSIC/STScI), A. de Ugarte Postigo (IAA-CSIC),
A.J. Castro-Tirado (IAA-CSIC), A. Fruchter (STScI),
A. Levan (U. Leicester/STScI), S. Guziy (IAA-CSIC),
J.M. Castro Cer��n (STScI), A. Guijarro (CAHA),
A. Aguirre (CAHA),  report:

"We have imaged the field of the GRB 030329 (GCN 1997
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 ) in four optical
colours with the 2.2 m (+BUSCA) telescope at the Observatorio de Calar
Alto on 20.9148-20.9670 UT May 2003. Aperture photometry of the
counterpart yielded Ic = 20.92 +/- 0.07. The zero point is based on the
star located at R.A.(J2000) = 10:44:42, Dec(J2000) = +21:32:31.6 with
I = 15.432 (GCN 2082
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 ). Further observations are planned."

This message may be cited.

A. Fruchter (STScI), A. Levan (U. Leicester/STScI), R. Hook
(ST-ECF/STScI), N. Pirzkal (ST-ECF), J. Gorosabel (STScI/IAA-CSIC),
P. Garnavich (Notre Dame), P. Nugent (LBNL), S. Thorsett (UCSB),
A. Castro-Tirado (IAA), J.M. Castro Ceron (STScI), C. Kouveliotou
(USRA), S.T. Holland (Notre Dame), J. Hjorth (U.  Copenhagen), and
N. Tanvir (U. Hertfordshire) report for the GOSH collaboration:

GRB 030329 has been observed at three epochs by HST:  15/16 April,
21/23 April and 12/13 May.  During all epochs UV (ACS/HRC), optical
(ACS/WFC) and NIR (NICMOS) images were obtained.  Additionally, in
the first epoch an ACS grism spectrum was taken, and in the second
epoch a STIS optical spectrum, delayed from the first epoch by a
gyrocope failure, was also obtained.  Here we report on aspects of
the imaging and grism spectroscopy which provide a unique contribution
from HST:  information on the nature of the host.

All the ACS images show the host extending to approximately ~0."5
from the OT to the west, with a PA of approximately 230 degrees.
In the most recent ACS/WFC images the OT has faded sufficiently to
allow a reasonable subtraction of the OT from the host, particularly
in the F435W and F606W filters where the blue color of the host
provides greater contrast against the redder OT than in the F814W
image.   We find the magnitude of the host to be approximately
V=22.7 +/- 0.3, where the uncertainty is dominated by the subtraction
of the OT and the unknown contribution to the host magnitude by
faint outerlying areas.  This apparent magnitude corresponds to an
absolute magnitude of about -16.5, very similar to that of the SMC.

The host can also be seen clearly in the UV ACS/HRC F250W images
taken on May 12.  The OT appears to lie at the end of a bar-like
structure approximately 0."25 across, which at the ~600 Mpc
angular-diameter distance of the GRB corresponds to a length of
about 800 pc.

The separation of the host from the OT can also be discerned in
the grism spectrum, where the emission lines of the host are seen
to be offset from spectral continuum of the OT.   Although the
spatial projection of the grism makes this somewhat uncertain, the
Halpha emission of the host appears to be fairly well centered on
host's blue light.

Images of the OT and host and the 2-d grism spectrum can be seen
at

http://www.stsci.edu/~fruchter/GRB/030329

[GCN OPS NOTE (23may03):  The extra zero in the URL was removed.]

K. Z. Stanek, D. W. Latham (Harvard-Smithsonian CfA) and M. E. Everett
(Planetary Sciences Institute) report:

We imaged the SN 2003dh (Matheson et al. GCN 2107
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 , 2120
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 ; Garnavich et
al. IAUC 8108, 8114; Stanek et al. astro-ph/0304173) associated with
the GRB 030329 with the FLWO 1.2-m telescope between May 20 UT 05:45
and May 23 UT 04:30 (51.75 and 54.7 days after the burst) using
standard R filter. The transient seems to brighten during that time:

         UT          R       dR    Filter    Texp
----------------------------------------------------
2003-05-20 05:45   21.575   0.07     R     4x900 sec
2003-05-21 05:00   21.689   0.11     R     4x900 sec
2003-05-22 05:45   21.429   0.08     R     4x900 sec
2003-05-23 04:30   21.321   0.09     R     5x900 sec

Observations using larger telescopes, also in other bands, are
strongly encouraged.

Any use of these data should include proper reference to this GCN.

S. Zharikov(OAN IA UNAM), V. Chavushyan, R. Mujica (INAOE) report:

We have observed the OT GRB030329 found by B.Peterson and P.Price (GCN 
1985
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 ) using the 2.1m telescope of the "Guillermo Haro" Observatory in 
Cananea, Sonora, Mexico with the Landessternwarte Faint Object 
Spectrograph and Camera (LFOSC). 
The I image was obtained on April 26 with  time of exposure 1200s.
Several R band images with time of exposure 1800s were obtained on April
28,30 and May 2,5,6 and 8 under good photometric conditions. Based on
filed photometry by A. Henden (GCN 2082
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 ) we estimate of OT magnitudes:

Date        Time(UT)      Band       Magnitude
---------------------------------------------- 
April 26      03:21         I         20.02(10)
April 28      03:20         R         20.49(7) 
April 30      03:24         R         20.60(8) 
May   2       03:28         R         20.64(8)
May   5       03:55         R         20.90(12) 
May   6       03:09         R         20.90(12) 
May   8       03:43         R         20.88(11)

This message may be cited.

A. Klotz, M. Boer (CESR France) and P. Martinez (ADAGIO observatory)
report magnitudes obtained by a team of the ADAGIO observatory at Belesta,
France (IAU station A05) using a 82 cm telescope and a Sbig ST8 Kaf1602E
CCD camera with a red filter.
All images are photometrically calibrated by Alain Klotz using the reference
stars given by A. Henden (GCNC 2023).

Red filtered measurements :
DATE                Observ.  Diam(mm) filter expo(s) Rmag +/-    observatory day-GRB
2003-04-23T22:28:00 OM&YM&PM     820  R     1440   20.11  0.07   Belesta 25.4475
2003-04-26T21:50:00 PMB&OM&PM    820  R      600   20.35  0.29   Belesta 28.4245
2003-04-30T21:15:00 YM&PM        820  R     1560   20.30  0.17   Belesta 32.4002
2003-05-03T21:24:00 PMB&OM&PM    820  R     2460   20.87  0.12   Belesta 35.4065

Observers :
OM&YM&PM  = Olivier Maury, Yves Megret, Patrick Martinez
PMB&OM&PM = Pierre-Michel Berg=E9, Olivier Maury, Patrick Martinez
YM&PM     = Yves Megret, Patrick Martinez

Complementary data (images) :
http://www.cesr.fr/~klotz/grb030329/results.html

This report may be cited.

A. Klotz and M. Boer (CESR France) report magnitudes of GRB 030329 obtained
at TAROT-Calern, at TBL-Pic du Midi and by members of AUDE (Association des
Utilisateurs de Detecteurs Electroniques - Electronic Device Users
Association). All images are photometrically calibrated by Alain Klotz using
the reference stars given by A. Henden (GCNC 2023).

Red filtered measurements :
DATE                Observers  Diam(mm) filter int(s) R      +/- observatory  day-GRB
2003-04-12T20:21:10 SD           600  R     5400   19.30  0.18   Lantelme     14.3628
2003-04-21T00:20:37 EB&al.       600  R     3000   20.25  0.75   Pic Du Midi  22.5291
2003-04-21T22:32:00 OM&YM&PM     820  R      600   19.9   0.4    Belesta      23.4537
2003-05-04T21:32:41 CC&SD        600  R     2760   22.74  0.37   Lantelme     36.4124

Infrared filtered measurements (afteglow not detected) :
DATE                Authors Diam(mm) filter int(s) mag    +/-    observatory day-GRB
2003-04-17T23:30:00 AK&CB       2000  K     3060  >18.2          Pic du Midi 19.4939
2003-04-18T01:26:00 AK&CB       2000  J     3960  >18.6          Pic du Midi 19.5745

Unfiltered measurements converted to the R band :
DATE                Authors Diam(mm) filter int(s) R      +/-    observatory day-GRB
2003-04-01T00:25:00 AK           200  C      360   16.72  0.45   Guitalens   2.5321
2003-04-04T20:30:00 TAROT        250  C      600   18.55  0.36   Calern      6.3689
2003-04-06T21:48:21 ML           318  C     2550   18.58  0.33   Dax         8.4234
2003-04-07T22:05:00 TM&BC        600  C      400   18.68  0.23   Pic du Midi 9.4349
2003-04-08T20:30:00 TAROT        250  C      600   18.81  0.44   Calern     10.3690
2003-04-21T22:05:00 OM&YM&PM     820  C      900   19.93  0.15   Belesta    23.4315

Observers
AK        = Alain Klotz
ML        = Mathieu Lahitte
TM&BC     = Thierry Midavaine & Bernard Christophe
SD        = Serge Deconhiout
AK&CB     = Alain Klotz & Coralie Berteloite
OM&YM&PM  = Olivier Maury, Yves Megret, Patrick Martinez
EB&al.    = Eric Barbotin, Cathy Dupeyre, Alain Laffont, Audrey Cazenave
CC&SD     = Cyril Cavadore & Serge Deconhiout

Complementary data (images) :
http://www.cesr.fr/~klotz/grb030329/results.html

This report may be cited.

The XMM-Newton SOC has scheduled a Target of Opportunity
observation of GRB 030329 in revolution 635 (28th to
30th of May 2003). Details of the instrumental setup
can be found at (Observation ID 0128531501):
http://xmm.vilspa.esa.es/external/xmm_sched/sched_obs_srch_frame.shtml

H. Cheng, M. Bayliss, D. Reichart, J. Moran, M. Nysewander, M. Schwartz,
and P. Holvorcem report on behalf of the UNC GRB team of the FUN GRB
collaboration:

We observed the afterglow (Peterson & Price, GCN 1985
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 ) of GRB 030329
(Vanderspek et al., GCN 1997
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 ) with the 32-inch Tenagra II telescope in
IcRcVIc on April 2nd and 3rd, in IcIc on April 4th and 5th, and in Ic on
April 6th, 7th, 8th, 9th, and 10th.  Between April 2nd and 10th, we find
that the afterglow faded from Ic = 16.9 mag to Ic = 18.9 mag.  Our 1-sigma
error bars are typically less than 0.02 mag.

Fitting a four-parameter model to the data, where the parameters are the
temporal index alpha, the spectral index beta, a normalization parameter,
and a parameter that measures the level of of systematic (i.e.,
non-statistical) fluctuations in the light curve, we find that alpha =
-1.70(+0.13)(-0.14), beta = -1.38(+0.20)(-0.20), and that the fading
afterglow is fluctuating at the 17.5(+3.8)(-3.5)% level at these times.

We note that the measured spectral index is too steep given the measured
temporal index and the post-jet break time relations of Sari, Piran, &
Halpern (1999, ApJ, 519, L17).  Possible explanations include:

1. The light curve had not yet reached its asymptotic temporal index, which
if the afterglow is unextinguished would be alpha = -2.76 +- 0.20 if the
cooling break is redward of the observed bands or alpha = -3.76 +- 0.20 if
the cooling break is blueward of the observed bands; or

2. The light curve is extinguished.  Although this does not appear to be
the case at earlier times, this could be the case at later times if dust
was destroyed within the initial opening angle of the jet, but then the jet
expanded laterally behind undisturbed dust.

We have noticed a minor numerical error near the end of GCN 2254
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 .  Here
is a corrected (and slightly expanded) version:

H. Cheng, M. Bayliss, D. Reichart, J. Moran, M. Nysewander, M. Schwartz,
and P. Holvorcem report on behalf of the UNC GRB team of the FUN GRB
collaboration:

We observed the afterglow (Peterson & Price, GCN 1985
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 ) of GRB 030329
(Vanderspek et al., GCN 1997
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 ) with the 32-inch Tenagra II telescope in
IcRcVIc on April 2nd and 3rd, in IcIc on April 4th and 5th, and in Ic on
April 6th, 7th, 8th, 9th, and 10th.  Between April 2nd and 10th, we find
that the afterglow faded from Ic = 16.9 mag to Ic = 18.9 mag.  Our error
bars are typically less than 0.02 mag (1 sigma).

Fitting a four-parameter model to the data, where the parameters are the
temporal index alpha, the spectral index beta, a normalization parameter,
and a parameter that measures the level of systematic (i.e.,
non-statistical) fluctuations in the light curve, we find that alpha =
-1.70(+0.13)(-0.14), beta = -1.38(+0.20)(-0.20), and that the fading
afterglow is fluctuating at the 17.5(+3.8)(-3.5)% level at these times.

Furthermore, these fluctuations appear to be chromatic in nature.

We note that the measured spectral index is too steep given the measured
temporal index and the post-jet break time relations of Sari, Piran, &
Halpern (1999, ApJ, 519, L17).  Possible explanations include:

1. The light curve had not yet reached its asymptotic temporal index, which
if the afterglow is unextinguished would be alpha = -2.76 +- 0.40 if the
cooling break is redward of the observed bands or alpha = -3.76 +- 0.40 if
the cooling break is blueward of the observed bands; or

2. The light curve is extinguished.  Although this does not appear to be
the case at earlier times, this could be the case at later times if dust
was destroyed within the initial opening angle of the jet, but then the jet
expanded laterally behind undisturbed dust.

K. Z. Stanek, D. Bersier, M. Calkins, D. L. Freedman and T. Spahr
(Harvard-Smithsonian CfA) report:

We continued imaging of the SN 2003dh (Matheson et al. GCN 2107
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 , 2120
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 ;
Garnavich et al. IAUC 8108, 8114; Stanek et al. astro-ph/0304173)
associated with the GRB 030329 with the FLWO 1.2-m telescope between
May 26 UT 05:00 and May 29 UT 05:00 (57.7 and 60.7 days after the
burst) using standard R_c filter. The increase in brightness by >0.3
mag observed by Stanek et al. (GCN 2244
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 ) between May 21 and May 23 UT
was followed by a decay of ~0.3 mag and then by an increased scatter
in the light curve:

         UT          R       dR    Filter    Texp
----------------------------------------------------
2003-05-26 05:00   21.612   0.06     R     5x900 sec
2003-05-28 04:50   21.456   0.07     R     4x900 sec
2003-05-29 05:00   21.617   0.09     R     4x900 sec

The figure showing the light curve since May 20 UT can be accessed at:
http://cfa-www.harvard.edu/~kstanek/jitter.jpg

We should stress that we have a very extensive data set for this
object obtained with exactly the same instrumentation and this "jitter
episode" is very unusual when compared to the whole data set and we
strongly believe that it is real and it might continue.  Therefore,
observations using larger telescopes, also in other bands, are
strongly encouraged.

Any use of these data should include proper reference to this GCN.

R. Burenin, R. Sunyaev, M. Pavlinsky, D. Denissenko, O. Terekhov,
A. Tkachenko (IKI); Z. Aslan, O.Golbasi, I. Khamitov (TUG); M.A. Alpar
(SU); U. Kiziloglu, A. Baykal (METU); I. Bikmaev, N. Sakhibullin, V.
Suleymanov (KSU)


report:

We observed the GRB 030329 afterglow with 1.5-m Russian-Turkish
Telescope RTT150 at Bakyrlytepe, Turkey. Our data for May 20 -- 28 are
consistent with constant flux of the OT. Using the photometry by Henden
(GCN 2082
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 ) we measured the following R magnitudes for the OT:

Date  UT     R     err
05-20 21:45  21.65 0.28
05-21 21:20  21.41 0.06
05-22 20:30  21.60 0.08
05-24 21:15  21.40 0.10
05-28 21:10  21.55 0.06

This message may be cited.

S. Zharikov, G. Tovmassian (OAN SPM IA UNAM, Ensenada, Mexico)
 report:
 
 We have observed the OT GRB030329 found by B.Peterson and P.Price (GCN 
 1985
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 ) using 1.5m telescope of OAN-SPM Observatory, BC, Mexico. 
A set of exposures in VR Bessel filters was obtained  of 2 June under 
photometric and good seeing conditions.  
Based on field photometry by A. Henden (GCN 2082
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 ) 
we estimate OT (or its host galaxy?)  magnitudes:

2 June
 <Tobs>      Texp.   Filter  Mag.
 
 UT 6:00    2400sec   V    21.86(10)
 UT 5:15    3000sec   R    21.42(7)

The R magnitude no changed during 20 May up to 2 June.
(see Burenin et al., GCN 2260
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 ).

 This message may be cited.

A. Pramesh Rao and C. H. Ishwara Chandra (NCRA, Pune),
D. Bhattacharya (RRI, Bangalore) and A.J. Castro-Tirado (IAA, Granada)
report on behalf of a larger collaboration:

The afterglow of GRB030329 (Peterson & Price, GCN 1985
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 ) was observed
with the GMRT for about 5 hours on May 31, 2003. The observations were at
1288  MHz with a bandwidth of 12MHz and effective angular resolution of
~3.5". The flux density of the source seen at the position of the GRB on
31 March and 01 April 2003 (Rao et al, GCN 2073
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 ) has increased to 1.1 mJy
confirming that the radio source is related to the GRB.

The details of the GMRT measurements of GRB030329 at 1288 MHz:

Date                        Time               Flux Density

31 May 2003                14-18 UT         1100+/-150 microJy
31 March/01 April 2003     14-22 UT          330+/-100 microJy

The quoted error bars are 2-sigma, and include systematic errors of
calibration.

Note that the flux density at 31 March/01 April epoch has been
revised upwards in comparison to that reported in GCN 2073
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 ,
following a better absolute flux density calibration.

This message may be cited.

S. Zharikov (IA OAN UNAM) reports:
 
The right magnitude of GRB030329 OT 
in R band of  31 March, 2003 at 
UT 7:49 was 16.48(3).

This message may be cited.

Trushkin S.A. (SAO RAS) on behalf of the SAO-IKI collaboration  report:

We have observed GRB 030329 during four sets with RATAN-600 radio telescope,
the mean flux densities of the radio counterpart are given in the table:

Frequency  3-7 Apr  13-21 Apr   1-7 May  15-31 May
-------------------------------------------------
 GHz       mJy +-    mJy +-    mJy +-   mJy +-
-------------------------------------------------
 3.9       49  10    15  3     15  3    10  3
 7.7       33   5    28  5     15  3    18  3
11.2       20   5    47  7     32  6    19  4

The spectral index varied  from -0.7 to +1.1, +0.7, +0.75
respectively with rms ~0.15.
The May indices are consistent with Nobeyama data (Cir.N2089).

A.Tiengo (IASF-Milano), S.Mereghetti (IASF-Milano) and N.Schartel
(XMM-Newton SOC, Villafranca) report:

A 24 hour long observation of GRB030329 has been obtained with XMM-Newton
starting at 21 UT on May 28, 2003. After rejecting high background time
intervals, the net exposure time in the EPIC instrument is about 40 ks.

The X-ray afterglow is detected at a level of (7+/-3)x10^-15 erg cm^-2
s^-1 (observed flux in the 2-10 keV range). This value is consistent with
the late time (t>1 day) flux evolution as a power law with index ~1.9, as
reported by Tiengo et al. (astro-ph/0305564).

The X-ray spectrum is well fit by a power law with photon index 2.2+/-0.4
and absorption <9x10^20 cm^-2.

This message may be cited.

M.A. Ibrahimov, I.M. Asfandiyarov, B.B. Kahharov (UBAI), A.Pozanenko (IKI),
V.Rumyantsev (CrAO), G.Beskin (SAO), I.Zolotukhin, A.Birykov (SAI MSU)
report:

We have observed the OT GRB030329 found by B.Peterson and P.Price (GCN 1985
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 )
with 1.5m telescope of Maidanak High-altitude Observatory (UBAI). Several
VBR Bessel images were obtained in May and June 2003. Based on the field
photometry by A. Henden (GCN 2082
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 ) we estimate the OT magnitudes:

 --------------------------------------------
 Date2003  Mid UT  exp   fltr   mag     err
 --------------------------------------------
 May 07    17:00   1800    R    20.72  0.09
 May 07    17:58   3000    B    22.77  0.30
 May 07    18:33   1800    V    22.20  0.31
 May 13    17:07   1200    R    20.93  0.43
 May 15    16:46   3300    R    21.16  0.21
 May 17    16:33   2100    R    21.76  0.20
 May 17    17:19   2400    B    21.86  0.27
 May 19    16:32   1800    R    21.53  0.19
 May 19    17:29   3600    B    22.59  0.16
 May 21    17:33    600    R    20.91  0.18
 May 22    17:00   2700    R    21.15  0.09
 Jun 01    16:55   2400    R    21.77  0.19

Using our previous observations (GCN 2219
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 ) we can determine that within the
error bars the OT brightness did not change in B filter over the period from
May 3 till 19.  Our data in R filter taken on May 7 and June 1 are
consistent with the values reported by S.Zharikov et al. (GCN 2245
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 , 2265
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 ).
The data on May 19 are consistent with measurement by K.Stanek et al. (GCN
2244
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 ) taken 13 hrs later.

Based on our "R" data set obtained with the same instrument we can conclude
that the OT re-brightness took place in May 21-22.  However there are
apparent differences in brightness estimations in the nearest epochs of the
observations obtained by the other teams in May 21-22.

The magnitude on May 21 differs from that estimated 12 hours earlier (GCN
2244
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 ). The magnitude on May 22 differs from that estimated 3.5 hours later
(R. Burenin et al., GCN 2260
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 ).  Taking into account published brightness
estimations one may suppose that during the period of May 21-22 the OT
experienced brightness variations as suggested by K.Stanek et al. (GCN 2244
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 ,
2259
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 ). However, the indicated differences are marginal (3.7 sigma), and to
confirm the variations cross-calibration of the data obtained by different
teams on May 21-22 is necessary.  If brightness variation will be confirmed,
such kind of variations should be considered as the shortest ones observed
to date for the late afterglows.

The Maidanak data for May 21, 22 can be accessed at
http://grb.rssi.ru/GRB030329/, and the file names are:
030329_030521R_UB.fits and 030329_030522R_UB.fits

This message may be cited.

I. Khamitov (TUG), I. Bikmaev, A.Galeev, N. Sakhibullin, V. Suleymanov (KSU);
Z. Aslan, O.Golbasi(TUG), S.Ozer (AU); M.A. Alpar (SU); U. Kiziloglu, A. Baykal(METU);
R. Burenin, R. Sunyaev, M. Pavlinsky, D. Denissenko, O.Terekhov, A. Tkachenko (IKI)

  Report:

  We observed the GRB 030329 target  with 1.5-m Russian-Turkish
Telescope RTT150 at Bakyrlytepe, Turkey, in June-July, 2003, by
using Andor CCD. Based on the photometry by Henden (GCN 2082
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 ) we 
measured the following Rc magnitudes for the target:

 Date        t-t0   Rc     dR
 2003-06-02 65.322 21.65  0.07
 2003-06-03 66.303 21.67  0.06
 2003-06-23 86.314 21.80  0.10
 2003-06-29 92.338 21.83  0.10
 2003-07-02 95.334 21.83  0.17
 2003-07-03 96.309 21.91: 0.28

  Although there is some indication of a systematic fading, the
errors are large for obvious reasons and we are already near the
limiting   magnitude at this high zenith distance. We will therefore 
discontinue the observations for this summer season.

  This message may be cited.

G. Kosugi, Y. Mizumoto, Y. Ohyama, K. S. Kawabata, and K. Aoki
(Subaru Telescope, NAOJ), report:

Spectra of GRB 030329 (H2656, Vanderspek et al, GCN 1997
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 ) optical
transient (Peterson & Price, GCN 1985
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 ) were obtained using the
Subaru 8.2m telescope and FOCAS (Faint Object Camera And Spectrograph)
with the wavelength coverage of 4700 to 9400A (R=700) on June 22.3 UT
(85 days after the burst).

Compared with the previous data (May 8 and 9 UT : 40 days after the
burst, Kawabata et al. IAUC 8133), we found that several nebular
phase lines ([OI] 6300/6364, [CaII] 7291/7323, etc.) began to emerge
out of the photospheric phase supernova spectrum.

This message may be cited.

A.Volvach, I.Strepka (CrAO) on behalf of CrAO/IKI/SAO collaboration report:

We have observed the radio afterglow position (E.Berger et al,  GCN2014
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 ) of
GRB030329 (R. Vanderspek et al, GCN1997
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 ) in June 26  at 4.8GHz, in July 8 at
22GHz, and in September at 4.8 and 8GHz with 22-m radio telescope RT-22 of
Crimean Astrophysical Observatory. The radio source was detected at 22 GHz
and upper limits have been obtained for other frequencies. The flux
densities are:

Date,UT   Frequency  Duration    Flux density
            GHz         hrs           mJy
Jun. 26     4.8         2        21.0 (3 sigma upper limit)
Jul. 08     22          2         6.9 +-2.3
Sep. 23      8          2         9.0 (3 sigma)
Sep. 25     4.8         3         7.5 (3 sigma)

The sensitivity at 4.8 GHz was significantly improved in September with
introducing in operation a cryo-radiometer. In September we detected a
signal at 4.8 GHz, however the beam of RT-22 (12 arcmin) covers 3 sources
found in NVSS (Condon et al. 1998, AJ, 115, 1693).The upper limit of flux
density on Sep. 25 includes statistical errors and uncertainty of spectral
indices of the 3 sources.

The message may be cited.

The XMM-Newton SOC has scheduled a Target of Opportunity

observation of the field of GRB 030329 in revolution 734 

(12th to 13th of December 2003). Details of the instrumental 

setup can be found at (Observation ID  0128531601):

http://xmm.vilspa.esa.es/external/xmm_sched/sched_obs_srch_frame.shtml

A. V. Filippenko, R. Chornock, and R. J. Foley, University of California,
Berkeley, report that CCD spectra (range 310-940 nm) of SN 2003dh, associated
with GRB 030329 (GCN 1985
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 ; GCN 2107
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 ), were obtained on Dec. 21 UT with the
Keck I 10-m telescope (+LRIS). Skies were clear, the seeing was about 1",
and the exposure time was 2.5 hours (five dithered half-hour integrations).
The object continues to exhibit broad [O I] 630 nm emission typical of Type
Ib/Ic supernovae in the nebular phase (e.g., Foley et al. 2003, PASP, 115,
1220). There is also evidence for weak, significantly narrower [Ca II] 730 nm
emission. There may be some weak, broad features in other parts of the
spectrum, but subtraction of a template spectrum of the host galaxy (which
dominates the continuum at this time) will be necessary to confirm these.

S. Dado [Technion], A. Dar [Technion] and A. De Rujula [CERN] report:

Taylor, Frail, Berger and Kulkarni [1] reported the discovery of a second
compact radio source in the afterglow of GRB 030329 at an angular distance
of 0.28 +\- 0.05 mas from the main source on day 51.3 after burst, which
was not resolved in their VLBI observations at other epochs. This
separation is "hyperluminal": the relative mean sky-projected-velocity is
> 19c. A transient strong rebrightening of the second radio source is
consistent with the reported "jitter"  first seen in observations of the
optical afterglow that began on day 51.75 (GCN 2224
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  [2], GCN 2259
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  [3]).
At that late time, the optical afterglow of GRB 030329/SN 2003dh is
expected to be dominated by the supernova. The spectroscopic resolution of
the afterglow into the individual contributions of the SN and GRB [2]
indicates that the GRB contribution rebrightened by a factor 2 or more.
An analogous rebrightening of the second radio source may explain why
it was resolved only on day 51.3.

The discovery [1] of a hyperluminal compact source may pin down the origin
of GRBs [5]. We encourage prompt and follow-up VLBI observations of XRFs.
In the cannonball model the source separation observed by Taylor et al. is
the expected one [5], and both GRBs and XRFs are produced by hyperluminal
plasmoids ejected in SN explosions. Relative to GRBs, XRFs are selectively
viewed at closer distances, and at viewing angles typically 3 times larger
[6]. This makes them very attractive targets for radio searches of the
expected hyperluminal motions, in particular promptly after the burst.

[1] astro-ph/0405300:  G.B. Taylor, D.A. Frail, E. Berger, S. Kulkarni
[2] GCN 2224
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 : K.Z. Stanek, D.W. Latham, M.E. Everett
[3] GCN 2259
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 : K.Z. Stanek, D. Bersier, M. Calkins, D.L. Freedman, T. Spahr
[4] astro-ph/0307435: T. Matheson et al.
[5] astro-ph/0406325: Dado, A. Dar, A. De Rujula
[6] astro-ph/0309294: S. Dado, A. Dar, A. De Rujula