GRB 041006
GCN Circular 2832
Subject
GRB 041006: GETS Optical Afterglow Observation
Date
2004-11-05T04:25:03Z (21 years ago)
From
Kenzo Kinugasa at Gunma Astro. Obs/Japan <kinugasa@astron.pref.gunma.jp>
K. Kinugasa (Gunma Astronomical Observatory) and K. Torii (Osaka U.)
report:
Starting at 12:50:19 UT on 2004 October 6 (32 minutes after the burst
trigger), the sky area of GRB041006 (Galassi, et al. GCN 2770) was
observed with the GETS (0.25-m robotic telescope equipped with
unfiltered CCD in the Gunma Astronomical Observatory). The observation
continued for 6.5 hours and 30-s exposure frames were obtained.
We stacked 20 original frames into a single frame and find that the
optical afterglow (Da Costa, et al. GCN 2765) is detected in the
stacked frames. Between 12:57 and 14:55 UT (mean epoch), we obtained
10 independent measurements and the afterglow faded from Rc=17.8 to
Rc=18.7 by using a comparison star from Henden's calibration (GCN 2801).
After 15:02 UT, intermittent clouds came to cover the field of view and
the afterglow was not detected.
GCN Circular 2830
Subject
GRB 041006: Optical Observations
Date
2004-11-04T06:28:19Z (21 years ago)
From
Grant Williams at Steward Observatory <gwilliams@as.arizona.edu>
G. Williams, X. Fan, A. Diamond-Stanic, M. Bayliss, D. Reichart, S. Shaw,
A. Homewood, D. H. Hartmann, and M. Schwartz report on behalf of the MMTO,
U. North Carolina, and SARA GRB teams of the FUN GRB collaboration:
We observed the afterglow location (Da Costa et al., GCN 2765) of GRB
041006 (Galassi et al., GCN 2770) in Bg'VRc beginning 14.9 hours after the
burst. Using the field calibration of Henden (GCN 2801), we report the
following magnitudes:
Start Mean Time Filter Exposure Magnitude Telescope
Date Since GRB Time (sec) (1)
(hours) x Exposures
Oct 7.134 15.127 Rc 300 x 5 >19.3 0.9m SARA
Oct 7.153 15.582 B 300 x 5 >18.2 0.9m SARA
Oct 7.110 16.250 Rc 180 x 36 >19.3 0.6m MO(2)
Oct 7.172 16.426 V 300 x 14 21.2+/-0.6 0.9m SARA
Oct 7.280 18.408 g' 300 x 2 21.75+/-0.08 2.3m Bok
(1) Limiting magnitudes are 2 sigma.
(2) Morehead Observatory
Previously reported in GCN 2799, the SARA observations are updated now
that the field calibration is available.
A light curve is available at:
http://www.physics.unc.edu/~mbayliss/grbdata/grb041006lc.eps
GCN Circular 2829
Subject
GRB041006, late-time optical photometry
Date
2004-11-04T03:51:19Z (21 years ago)
From
Peter Garnavich at U of Notre Dame <pgarnavi@nd.edu>
A. Garg, C. Stubbs, P. Challis, K. Z. Stanek (CfA), and
P. Garnavich (Notre Dame)
We imaged the field of the GRB 041006 afterglow (Da Costa, Noel,
& Price, GCN 2765) with the 6.5m Clay telescope of the Magellan
Observatory on Nov. 3.1 (UT). A total exposure of 900s in
the R filter was obtained with the MagIC instant imager in
0.6 arcsec seeing. We compared the Magellan image to data taken with
the Vatican Advanced Technology Telescope (VATT) less than 2 days
after the burst (GCN 2792) and detect a source at the
position of the afterglow. Assuming the star 9" west and 4" north
of the afterglow has a brightness of R=21.9 mag (based on the VATT
calibration), we estimate the source in the Magellan images
to be R=24.4 +/- 0.2 mag.
This is approximately 2 mags brighter than the extrapolation of
first 4 days of the afterglow light curve. It is also marginally
fainter than the brightness estimate of Bikmaev et al. (GCN 2826)
on Oct. 18, implying that the source is variable and is not a structure
on the host galaxy. We conclude that the light is dominated by
a supernova that reached its peak brightness in the past two weeks.
This message can be cited.
GCN Circular 2826
Subject
GRB041006: RTT150 Optical Observations
Date
2004-10-19T17:43:19Z (21 years ago)
From
Irek Khamitov at TUG <irekk@tug.tug.tubitak.gov.tr>
I. Bikmaev, N. Sakhibullin (Kazan State University),
M.A. Alpar (Sabanci U.), U. Kiziloglu, S. Balman (METU),
Z. Aslan, I. Khamitov (TUG),
R. Burenin, M. Pavlinsky, R. Sunyaev (IKI),
We observed the afterglow of GRB 041006 (G. Da Costa et al., GCN 2765,
P.A. Price, GCN 2766), discovered by HETE (M. Galassi et al., GCN 2770),
with Russian-Turkish 1.5-m telescope (Bakyrlytepe, TUBITAK National
Observatory, Turkey).
We made 48 x 300 sec images in R between Oct. 18, 19:50 UT, and Oct.
19, 00:37 UT (12.4 d after the burst) using the imaging ANDOR CCD. The
seeing was 1.3-1.6" and weather was clear.
We detected the source at combined image with m_R = 24.0+/-0.2. For
calibration of the R band images we used the reference stars reported in
(A. Henden, GCN 2801).
Part of 8 x 8 arcmin combined RTT150 image of the field and the source
location is presented at:
http://www.tug.tubitak.gov.tr/~irekk/grb/grb041006/GRB041006_Oct18.jpg
Our measurement of R magnitude shows clear deviation on the
extrapolation of the early detections on R band light curve and
confirms our previous OT detection above the extrapolation
(S.Balman et al., GCN 2821).
We, probably, see the supernova re-brightening, or the host galaxy.
Supernova bump is more probable since the OT is outside the center of
the host galaxy (J.Fynbo et al., GCN 2802, S. Covino et al., GCN 2803)
and its brightness is still higher than that of the host.
This message can be cited.
GCN Circular 2821
Subject
GRB041006: RTT150 Optical Observations
Date
2004-10-17T20:51:32Z (21 years ago)
From
Solen Balman at METU <solen@astroa.physics.metu.edu.tr>
S. Balman (METU), I. Bikmaev (KSU), U. Kiziloglu, A. Baykal (METU), E.
Gogus, M.A. Alpar, U. Ertan (Sabanci U.), Z. Aslan, I. Khamitov,
K. Uluc (TUG), N. Sakhibullin (KSU), R. Burenin, M. Pavlinsky (IKI),
R. Sunyaev (IKI, MPA) report :
We observed the field centered on the optical afterglow (GCN
2765, 2766) of GRB 041006 (=H3570) discovered by HETE (GCN 2770)
with the TUG (TUBITAK National Observatory, Turkey) 1.5-m
Russian-Turkish Telescope (RTT150).
We obtained 6x180 s R band images on 2004.10.10 (3.53 d after
burst) starting at 01:01:48 UT,
and 10x180 s R band images on 2004.10.11 (4.51 d after burst)
starting at 00:32:34 UT, using the imaging Loral Lick3 CCD.
The seeing was 1.8" on 2004.10.10 and 1.6" on 2004.10.11.
Our 2 sigma upper limits are m_R > 22.64 (Oct 10.05) and m_R > 23.30
(Oct 11.03).
We further obtained 18X600 s R band images on 2004.10.14 between
21:32:32 UT (8.4 d after the burst) and 01:32:18, with RTT150 using
the imaging ANDOR CCD. The seeing was 1.3-1.6".
We detected the source at m_R = 23.8+/-0.25 (corresponding to 2 sigma
detection). For calibration of the R band images we
used the reference stars reported in GCN (2801).
An image of the field and the source location is presented at
(cf. GCN 2802, 2803) :
http://astroa.physics.metu.edu.tr/grb/grb041006/grb041006_rtt150.jpg
Our results in comparison with the extrapolation of the earlier
detections on the R band light curve are shown at :
http://astroa.physics.metu.edu.tr/grb/grb041006/grb041006_plot.gif
This message can be cited.
GCN Circular 2814
Subject
GRB041006: Near Infrared observations
Date
2004-10-16T08:46:26Z (21 years ago)
From
Kenzo Kinugasa at Gunma Astro. Obs/Japan <kinugasa@astron.pref.gunma.jp>
K. Kinugasa, and E. Nishihara (Gunma Astronomical Observatory) report;
The sky position of optical afterglow (Da Costa et al. GCN 2765) of
GRB041006 (Galassi et al. GCN 2770) was observed in J-, H-, and
Ks-band on the night of 2004 Oct. 6 at GAO, Gunma, Japan, using
the 1.5-m telescope and the IR Camera. The observation started at
14:40 UT (142 min after the GRB trigger).
We find no transient brighter than J~16.5, H~16.0, and Ks~14.0 at the
position of the optical afterglow (Da Costa et al. GCN2765) compared
with 2MASS JHK magnitudes.
This message may be cited.
GCN Circular 2808
Subject
GRB041006: Fading X-ray Afterglow Observed with Chandra
Date
2004-10-15T18:16:51Z (21 years ago)
From
Nat Butler at MIT/CSR <nrbutler@space.mit.edu>
GRB041006: Fading X-ray Afterglow Observed with Chandra
N. Butler, R. Vanderspek, H. L. Marshall, P. G. Ford, G. R. Ricker
(MIT), D. Q. Lamb (U.Chicago), and G. P. Garmire (PSU)
report:
Beginning at October 7.213 (t[burst] + 16.80 hr) and continuing until
October 8.286 (t[burst] + 42.57 hr), Chandra Low Energy Transmission
Grating Spectrometer (LETGS) observations were conducted of a field
centered on the optical afterglow candidate (Da Costa et al, GCN2765) for
GRB041006, which was localized by the HETE WXM instrument (Galassi et al,
GCN2770). We have detected a moderately bright, fading X-ray afterglow
consistent in position with the optical source. Over the 86.3 ksec of data
accumulation (livetime) for the Chandra observations, the mean counting rate
was 0.010 counts/s in the dispersed 1st order LETGS spectrum and 0.007
counts/s in the 0ther order. The source we detected faded in brightness
according to a power law, with a decay time slope of -1.0 +/- 0.1. We fit
the 0th order and 1st order data jointly, requiring 20 or more counts per
spectral bin. An absorbed power-law model provides an acceptable fit
(chi^2/nu = 66.2/63), with the following best-fit paramters over the
0.5-6 keV range:
dN/dE = A * exp[-nH*s(E)] * E^ (-gamma) ph cm^(-2) s^(-1) keV^(-1) ,
with:
A = (1.0+/-0.2) x 10^(-4) ,
gamma = 1.9+/-0.2 , and
nH = (1.1+/-0.5) x 10^21 cm^(-2).
The measured value of nH exceeds the anticipated Galactic column density
(nH = 2.9 x 10^20 cm^(-2)) in the source direction. We measure a
mean flux in the 0.5 to 6 keV band over the duration of the Chandra
observation of ~3.7 x 10^(-13) ergs cm^(-2) s^(-1).
Our analyses are continuing, and more detailed results will be posted at:
http://space.mit.edu/HETE/Bursts/GRB041006
We thank Harvey Tananbaum and the Chandra X-ray Observatory Operations
personnel, particularly Jeremy Drake and Brad Wargelin, for the impressive
promptness with which this observation was planned and carried out.
The preliminary results reported here may be cited.
GCN Circular 2804
Subject
GRB 041006 R observations in Loiano
Date
2004-10-15T11:32:26Z (21 years ago)
From
Corrado Bartolini at Universita di Bologna <bartolini@bo.astro.it>
G. Greco, C. Bartolini, A. Guarnieri, A. Piccioni (Universita' di Bologna)
P. Ferrero (IASF/CNR, Bologna; Osservatorio e Universita' di Teramo),
G. Pizzichini (IASF/CNR, Bologna), E. Mazzotti Epifani (INAF, Oss. di
Capodimonte - Napoli) and R. Gualandi (INAF, Bologna Observatory) report:
On October 7, 2004 in clear sky conditions (seeing 2") we obtained
two R-band images (1200 sec X 2) of the OT of GRB 041006 (=HETE 3570)
reported by Da Costa, Noel and Price (GCN 2765) with the 152 cm telescope
in Loiano.We co-added the two exposures and used the following stars
in Henden's photometric calibration (GCN 2801):
RA Decl.
13.6373 1.221278
13.708797 1.202692
13.783485 1.302545
We find the following magnitude for the OT:
R = 22.22 +/- 0.13 at UT 22:40 (mean value).
Our images are available in a public directory from where it is possible
to retrieve them by sftp using:
hostname: ermione.bo.astro.it
username: publicGRB
password: GRB_bo
directory: GRB041006
GCN Circular 2803
Subject
GRB041006: VLT observations of the afterglow and host galaxy
Date
2004-10-14T11:16:39Z (21 years ago)
From
Daniele Malesani at SISSA-ISAS,Trieste,Italy <malesani@sissa.it>
S. Covino, D. Malesani, G. Tagliaferri, P. D'Avanzo, L.A. Antonelli,
G. Chincarini, M. Della Valle, F. Fiore, D. Fugazza, L. Stella,
on behalf of the MISTICI collaboration, report:
We observed the optical afterglow (Da Costa, Noel & Price, GCN 2765;
Maeno et al. GCN 2772) of GRB 041006 (Galassi et al., GCN 2770)
with the 8.2m ESO-VLT-UT2 (Kueyen) at Cerro Paranal. Observations
were carried out under good observing conditions (seeing 0.9")
with the FORS1 instrument.
The afterglow is clearly detected in the B, R and I bands. We report
the following magnitude for the object (calculate performing PSF photometry):
R = 23.59 +- 0.06 on 2004 Oct 11.121 UT
The decay seem therefore even steeper than that inferred from the previous
TNG observations (Fugazza et al., GCN 2782; D'Avanzo et al., GCN 2788).
In our coadded images, we also detect an extended emission surrounding
the afterglow, apparently 2.5" in size (18 kpc at z=0.712; Fugazza et al.,
GCN 2782; Price et al., GCN 2791). As suggested by Fynbo et al. (GCN 2802),
this is likely the host galaxy of GRB 041006. Performing PSF photometry,
we estimate that the contribution inside the afterglow PSF area is
likely very small. The afterglow is located inside the galaxy,
about 1" South East of its nucleus.
A snapshot centered about the GRB position is posted online at the following URL:
http://www.sissa.it/~malesani/GRB/041006
together with an updated light curve with all public data.
We acknowledge the excellent support from the observing staff at Paranal.
This message may be cited.
[GCN OPS NOTE (18:00 14oct04 UT) As per author's request, the line:
"The afterglow is located inside the galaxy, about 1" South West of its nucleus."
was changed to:
"The afterglow is located inside the galaxy, about 1" South East of its nucleus."
Line_breaks were also added.]
GCN Circular 2802
Subject
GRB041006: Optical observations and Potential host galaxy
Date
2004-10-14T10:17:18Z (21 years ago)
Edited On
2024-11-18T10:10:13Z (a year ago)
From
Johan U. Fynbo at U.Copenhagen <jfynbo@astro.ku.dk>
Edited By
Judith Racusin at NASA/GSFC <judith.racusin@nasa.gov> on behalf of Leo P. Singer at NASA/GSFC <leo.p.singer@nasa.gov>
J. P. U. Fynbo, B. L. Jensen, K. Pedersen, D. Watson, P. Jakobsson,
G. Bjornsson, J. M. Castro Cerón, H. Pedersen, J. Hjorth
(U. Copenhagen), D. Zucker (MPIA) and T. Pursimo (NOT) report:
"We have observed the field of GRB 041006 (Galassi et al., GCN #2770)
at two epochs with the 2.56m Nordic Optical Telescope using the
MOSCA instrument (R-band). At the position of the afterglow (Costa et
al., GCN #2735), we detect the following:
Date (UT 2004) | t_b+ | exptime | Seeing | mag.
------------------------------------------------------------
Oct. 06.96 10.8h 300s+3x600s ~0.8" R~20.5
Oct. 11.18 112.2h 5x600s ~1.9" R~23.6
The photometry is relative to the magnitude of a nearby star
as measured by Henden (GCN #2801). The source is clearly extended in
the 2nd epoch image (although the seeing was poor), so the potential
host galaxy is most likely contributing most of the flux.
A section of the 2nd epoch image can be seen at
http://www.astro.ku.dk/~brian_j/grb/grb041006 ."
GCN Circular 2801
Subject
GRB041006, BVRcIc field calibration
Date
2004-10-13T16:59:46Z (21 years ago)
From
Arne A. Henden at USNO/USRA <aah@nofs.navy.mil>
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 on the afterglow coordinates
(da Costa et al., GCN 2765; Yamaoka et al., GCN 2781)
for the HETE burst GRB041006 (trigget 3570; Galassi et al., GCN 2770)
with the USNOFS 1.0-m telescope on one marginally photometric
night. Stars brighter than V=13.5 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/grb041006.dat
The astrometry in this file is based on linear plate solutions
with respect to UCAC2. The external errors are less than 100mas.
The estimated external photometric error is about 0.03mag
and will be improved with additional calibration nights
later this week.
In particular, the stars calibrated by Fugazza et al. (GCN 2782)
and da Costa and Noel (GCN 2789) are present in the file, with
similar magnitudes within error.
As always, you should check the dates on the .dat file prior to
final publication to get the latest photometry. There is
a README file on the ftp directory to give you information
about the procedures used to calibrate these fields.
GCN Circular 2799
Subject
GRB 041006: SARA afterglow observations
Date
2004-10-13T01:08:37Z (21 years ago)
From
Dieter Hartmann at Clemson.U <hdieter@clemson.edu>
Scott Shaw (UGA), Autumn Homewood, Dieter H. Hartmann (Clemson)
Report on behalf of the Follow-Up-Network (FUN) GRB collaboration:
We observed a 6x6 arcminute field centered on the optical afterglow (GCN
2765, 2766) of GRB 041006 (=H3570) discovered by HETE (GCN 2770)
with the SARA 0.9 m Telescope at KPNO. Observations were carried out
under good seeing conditions with the AP7 CCD. We obtained 25 minutes
of exposure each in B and R, and 70 minutes in V. Observations started
at UT Oct. 7.6216, and ended Oct 7.7065. We do not detect the afterglow
in either the B-band or the R-band, but do detect it in V. Our B-band
limit is
estimated as B > 19.8, based on field star photometry described in GCN
2789.
The estimated R-band limit is R > 19.5, based on photometry described in
GCN 2782. The detection in the V-band yields a preliminary magnitude,
based
on photometry described in GCN 2789, of V = 20.9 +/- 0.2 (statistical
error).
The SARA home page can be found at
http://www.astro.fit.edu/sara/sara.html
This message may be cited, but we caution that the final photometry
remains to
be carried out with a larger set of calibration stars.
GCN Circular 2798
Subject
GRB041006, optical observation in CrAO
Date
2004-10-12T20:51:02Z (21 years ago)
From
Vasilij Rumjantsev at CrAO <rum@crao.crimea.ua>
V.Rumyantsev (CrAO), V.Biryukov (SAI, MSU), A.Pozanenko (IKI) report:
We have observed the OT found by G. Da Costa, N. Noel and P.A. Price
(GCN2765) of GRB041006 (HETE #3570, M. Galassi, et al. GCN2770) with AT-64
telescope of Crimean Astrophysical Observatory. Several 120 s exposure
images in R-band were taken between (UT) Oct.6 17:11 - 22:40 under moderate
weather conditions and poor seeing. After inspection only 21 images
between Oct.6 (UT)18:33-20:27 is used for further reduction. Additional
observation on Oct. 7 reveals no OT. The data reduction against seven USNO
A2.0 field stars results to following magnitude of the OT and limiting
magnitude for October 7
Mean UT, exposure, mag, S/N
Oct 6.81 21x120s 19.35R 3.8
Oct 7.85 64x120s >20.0R 3
We do not apply a possible correction to a brightness of the field stars
suggested by D. Fugazza et al. (GCN 2782), A. Monfardini et al. (GCN 2790)
and P. Garnavich, X. Zhao, T. Pimenova (GCN 2792).
This message may be cited.
GCN Circular 2794
Subject
GRB 041006 Optical afterglow observations
Date
2004-10-10T05:03:27Z (21 years ago)
From
Shashi Bhushan Pandey at State Obs.Nainital,India <shashi@upso.ernet.in>
Kuntal Misra and S. B. Pandey (ARIES NainiTal), on behalf of
larger Indian GRB collaboration
We observed several R_c band frames of the GRB 041006 optical afterglow,
determined the magnitudes in comparison with the stars A and B as reported
in GCN 2792 using 1.04-m telescope of ARIES Nainital India. The OT decayed
by ~ 0.5 mag from Oct 6.75 to Oct 6.91 UT.
Preliminary R_c - band magnitudes are:
Oct 6.776284 19.81 0.05
Oct 6.830509 20.00 0.05
Oct 6.862395 20.02 0.05
Oct 6.877175 20.18 0.06
The temporal flux decay index is ~ -1.0. We did not notice any considerable
steepening in the light curve using our data set.
This massage may be cited.
GCN Circular 2792
Subject
GRB 041006: BR observations with VATT
Date
2004-10-09T03:29:13Z (21 years ago)
From
Krzysztof Z. Stanek at CfA <kstanek@cfa.harvard.edu>
P. Garnavich, X. Zhao, T. Pimenova (Notre Dame)
We observed the field of the afterglow of GRB 041006 reported by Noel & Price
(GCN 2765) with the 1.8-m Vatican Advanced Technology Telescope (VATT) beginning
on Oct. 8.251 (UT) (1.74 days after the burst). Exposures totaling 25 minutes
in R and B were obtained in 1" seeing. Standard stars were also observed
and color terms applied to two local standards:
RA (J2000) Dec R B
Star A 00:54:47.044 +01:14:05.61 17.71 (04) 18.24 (04)
Star B 00:54:54.494 +01:15:47.81 16.28 (04) 17.95 (04)
showing that the USNO A2.0 red magnitudes are 0.4 mag too bright for this
field as noted by Fugazza et al. (GCN 2782) and that the B-mags are way
off.
The optical transient is measured to be R=22.31 (05) and
B=23.09 (06) mag. The reddening in this direction (Schlegel et al. 1998)
is E(B-V)=0.026 mag so the intrinsic color is B-R=0.737 mag. corresponding
to a power-law spectral slope of -1.0.
This message can be cited.
[GCN OPS NOTE (09oct04 13:00 UT): As per author's request,
the "2.25 days after" was changed to "1.74 days after".]
GCN Circular 2791
Subject
GRB 041006: Redshift confirmed
Date
2004-10-09T02:56:08Z (21 years ago)
From
Paul Price at IfA,UH <price@ifa.hawaii.edu>
P.A. Price (IfA, UH), K. Roth (Gemini), J. Rich, B.P. Schmidt, B.A.
Peterson (RSAA, ANU), L. Cowie (IfA, UH), C. Smith and A. Rest (CTIO)
report:
We have observed the optical afterglow of GRB 041006 (GCN #2765) with
the Gemini North Telescope + GMOS at 2004 Oct 7.36 UT. Observations
consisted of 4 integrations of 1800 sec with the R400 grating and a 1
arcsec slit. Inspection of a single frame reveals absorption lines at
6750A and 6810A, which we interpret as corresponding to the Ca II H and
K lines at a mean redshift of z = 0.716, in broad agreement with the
redshift of z = 0.712 proposed by Fugazza et al. (GCN #2782).
We thank the staff of Gemini North for performing these observations.
GCN Circular 2790
Subject
GRB041006: Liverpool Telescope optical observations
Date
2004-10-08T22:10:58Z (21 years ago)
From
Alessandro Monfardini at JMU/Liverpool Robotic Tele <am@astro.livjm.ac.uk>
A. Monfardini (Liverpool), C. Mottram (Liverpool J.M. Uni.), C. Guidorzi
(Liverpool), N. Tanvir (U. of Hertfordshire), C. Mundell (Liverpool),
I. Steele (Liverpool), R. Priddey (Hertfordshire), M. Hughes
(Hertfordshire), R. Smith (Liverpool), A. Gomboc (Liverpool), S. Fraser
(Liverpool), M. Bode (Liverpool), A. Newsam (Liverpool) report:
We observed the optical afterglow of GRB 041006 with the 2.0m Liverpool
Telescope on La Palma. We obtained BVRI imaging commencing 8.2 hours after
the burst. We report preliminary R-band estimates:
R = 20.4 +/- 0.1 mag at Oct 6.92 UT (exposure time = 600s)
R = 20.6 +/- 0.1 mag at Oct 6.98 UT (exposure time = 600s)
These values were derived applying zero points inferred from the Landolt
standard stars as cited in Fugazza et al (GCN 2782), which result in
measured magnitudes ~0.3 mag fainter than those given in the USNO
catalogue.
star RA Dec R mag err
----------------------------------------------------------
U0900_00213234 00:54:47.045 +01:14:05.60 17.75 +- 0.04
U0900_00213423 00:54:50.131 +01:12:10.33 18.90 +- 0.04
In summary, we confirm the R-band magnitude measured by Fugazza et al
(GCN 2782) at 7.07UT.
GCN Circular 2789
Subject
GRB 041006: Colour measurement
Date
2004-10-08T21:26:52Z (21 years ago)
From
Paul Price at IfA,UH <price@ifa.hawaii.edu>
G. Da Costa (RSAA, ANU) and N. Noel (IAC) report:
We have reduced our observations of the afterglow of GRB 041006 (GCN
#2765). From observations of several photometric standards taken the
same night, we find that the star at coordinates 00:54:37.96,
+01:13:00.7 J2000 (i.e. south west of the offset star in the finder from
GCN #2766) has B = 18.28 mag and V = 17.35 mag. From these, we estimate
that the afterglow had a B-V colour of approximately 0.28 +/- 0.03 mag
around 2004 Oct 6.58 UT.
GCN Circular 2788
Subject
GRB041006: break in the light curve
Date
2004-10-08T18:34:22Z (21 years ago)
From
Daniele Malesani at SISSA-ISAS,Trieste,Italy <malesani@sissa.it>
P. D'Avanzo, S. Covino, L.A. Antonelli, D. Fugazza, D. Malesani, F.
Fiore, F. Cocchia, N. Masetti, E. Pian, L. Stella (on behalf of the
Italian CIBO collaboration); V. Lorenzi and R. Barrena (INAF-TNG), report:
We observed again the optical afterglow (Da Costa, Noel & Price, GCN
2765; Maeno et al. GCN 2772) of GRB 041006 (Galassi et al., GCN 2770)
with TNG. Photometry was performed in the UBVRI bands under good
observing conditions (seeing 1.2").
We measure the following magnitude for the afterglow on Oct 8.10 UT
(1.59 days after the GRB):
R = 22.12 +/- 0.08
A comparison with our previous measurement (Fugazza et al., GCN 2782)
implies a dimming of 1.36 +- 0.09 mag. The corresponding decay index is
alpha = 1.20 +- 0.08 (F = K t^-alpha), significantly steeper than the
early-time value (alpha ~ 0.7: Fox, GCN 2768; Price, Da Costa & Noel,
GCN 2771; Yost et al., GCN 2776). A break in the light curve must
therefore be present, consistent with the suggestion of Kahharov et al.
(GCN 2775). The fading is confirmed in the other bands and is achromatic
within the errors.
We also observed again Landolt standard stars, finding the same
zeropoint than in our previous observation (Fugazza et al., GCN 2782) to
within 0.03 mag. We conclude that our calibration is correct and both
nights were photometric.
The light curve of this event, including all the published photometry,
can be found at the following URL:
http://www.sissa.it/~malesani/GRB/041006
This message can be cited.
GCN Circular 2787
Subject
GRB 041006: Radio Observations
Date
2004-10-08T18:01:23Z (21 years ago)
From
Alicia Soderberg at Caltech <ams@astro.caltech.edu>
A. M. Soderberg (Caltech) and D. A. Frail (NRAO) report on behalf of a
larger collaboration:
"On 2004 Oct. 7.25 UT (t ~ 18 hrs) we carried out follow-up
observations with the VLA at 8.46 and 4.96 GHz centered on the optical
afterglow (GCN 2765) of GRB 041006 (GCN 2770). Within a circle of
1-arcsec radius, there are no radio sources detected at either frequency.
We place 2-sigma upper limits of 82 and 118 microJy at 8.46 and 4.96 GHz,
respectively."
GCN Circular 2786
Subject
GRB041006, further submilllimetre observations
Date
2004-10-08T15:32:29Z (21 years ago)
From
Vicki Barnard at Joint Astro.Centre,Hawaii <vbarnard@jach.hawaii.edu>
V. Barnard, G. Schieven, R. Tilanus, J. Cox (all Joint Astronomy Centre),
R. Plume (University of Calgary), J-F. Lestrade (Observatoire de Paris)
report on behalf of the JCMT afterglow collaboration:
Further observations of GRB 041006 with SCUBA at the JCMT were made on
07/10/04 at mean epoch 13:00:00 UT. In good weather conditions, the
source was not detected, with an 850 micron result of (1.1 +- 1.7) mJy.
GCN Circular 2785
Subject
GRB 041006 : optical follow-up observation at Lulin Observatory
Date
2004-10-08T15:09:42Z (21 years ago)
From
Kuiyun Huang at IANCU <d919003@astro.ncu.edu.tw>
GRB 041006 : optical follow-up observation at Lulin Observatory
D. Kinoshita, Z.Y. Lin
K.Y. Huang, Y. Urata, K. Onda, W.H. Ip, T. Tamagawa
on behalf of Lulin GRB collaboration report:
" We have observed the optical afterglow reported by Costa et al. (GCN
2765) at 7.65 hr after the burst using Lulin 1-m telescope. The
afterglow's magnitude compared with USNOB-1 catalogue are:
Filter Exopsure UT Mag.
B 300s 19:57:08 20.1
R 300s 20:02:54 19.9
This message maybe cited. "
[GCN OPS (08oct04): Due to a disk-full error, this Circular
was issued with the wrong serial number. It has been changed
from 2807 to 2785.]
GCN Circular 2784
Subject
GRB 041006 : Optical follow-up observation at TAROT
Date
2004-10-08T14:59:37Z (21 years ago)
Edited On
2025-04-09T18:45:24Z (7 months ago)
From
Jean-Luc Atteia at Lab d Astrophys.,OMP,Toulouse <atteia@ast.obs-mip.fr>
Edited By
Judith Racusin at NASA/GSFC <judith.racusin@nasa.gov> on behalf of Tyler Barna at University of Minnesota <tylerpbarna@gmail.com>
Klotz, A., Boer M., G. Stratta, and Atteia J-L. report:
TAROT observed the HETE alert #3570
on 2004 Oct. 06, 19:55 UT (middle time).
The telescope took a series of 12 x 100-s unfiltered images
of the afterglow reported by
G. Da Costa et al. (GCN 2765)
We co-added frames to obtain a single image.
Comparing to the USNO-1B catalog and DSS
image, we are able to detect all stars
brighter than R=19.4 but the afterglow
is not visible.
The candidate proposed by Da Costa et al. (GCN 2765)
is not detected at the 3 sigma level. We conclude that the
afterglow had a magnitude R > 19.4.
This message may be cited
[GCN OPS (08oct04): Due to a disk-full error, this Circular
was issued with the wrong serial number. It has been changed
from 2806 to 2784.]
GCN Circular 2782
Subject
GRB041006: Optical photometry and spectroscopy at TNG
Date
2004-10-07T17:55:28Z (21 years ago)
From
Angelo Antonelli at Obs. Astro. di Roma <angelo@coma.mporzio.astro.it>
D. Fugazza, F. Fiore, S. Covino, L.A. Antonelli, P. D'Avanzo, F. Cocchia,
D. Malesani, E. Pian, L. Stella (on behalf of the Italian CIBO collaboration);
V. Lorenzi and G. Tessicini (INAF-TNG), report:
"We observed the optical afterglow (Da Costa, Noel & Price, GCN 2765;
Maeno et al. GCN 2772) of the X-ray rich GRB 041006 (Galassi et al.,
GCN 2770) with the Italian 3.6m telescope TNG at the Canary Islands.
Both photometric and spectroscopic observations were carried out using
DOLORES under good observing conditions (seeing of ~1").
From two R-band images (2x120 s), we obtain the following magnitude on
Oct 7.07 UT (0.557 days after the GRB):
R = 20.76 +- 0.04.
This value is based on a calibration with Landolt standard stars.
We list below magnitudes we obtain for the two stars close to the
optical transient:
star RA Dec R mag err
- ---------------------------------------------------------
U0900_00213234 00:54:47.045 +01:14:05.60 17.75 +- 0.04
U0900_00213423 00:54:50.131 +01:12:10.33 18.90 +- 0.04
Note as the above magnitudes are fainter than those given by USNO,
by about 0.4 mag. This may indicate a non photometric night, or
that the USNO catalog is not particularly accurate in this region
of the sky.
Starting on Oct 7.10 UT, a low resolution (R ~ 1000) spectrum of the
transient was also obtained. Observations consisted of three exposures,
for a total exposure time of 1 hour, and cover the full spectral range
3800-8000 A. The observed spectrum has a relatively low signal-to-noise
and does not show any strong obvious emission line. The most prominent
absorption feature is at 4800 A. If this feature is identified with the
blend of the MgII lambda2803,2796 doublet, a redshift of z=0.712 is
implied. If this is the case, the MgI lambda2852, FeII lambda2382,2374
and FeII lambda2344 transitions might coincide with other absorption
features in the spectrum, although each single line is not statistically
significant.
At the estimated redshift the isotropic-equivalent gamma-ray energy of
the burst is E = 1.5x10^52 erg (2-400 keV), adopting the fluence reported
by Galassi et al. (GCN 2770),
We are particularly grateful to the TNG staff for their remarkable
support to these observations."
This message is citeable.
-------------------------------------------------
This mail sent through IMP: http://horde.org/imp/
GCN Circular 2781
Subject
GRB 041006: presice astrometry
Date
2004-10-07T17:17:55Z (21 years ago)
From
Hitoshi Yamaoka at Kyushu U., VSNET-GRB collab. <yamaoka@rc.kyushu-u.ac.jp>
H. Yamaoka (Kyushu Univ.), K. Ayani (Bisei Astronomical Observatory)
and K. Itagaki (Teppo-cho, Yamagata) report:
We performed astrometry with the R-band Bisei image (Ayani and
Yamaoka, GCN 2779) and an unfiltered-CCD image taken by KI with 0.60-m
reflector on Oct. 6.65 UT. The reference frame is the 2MASS catalog
(7 stars) and the UCAC2 catalog (44 stars), respectingly. Fitting
error for each coordinate is better than 0".1. The mean of the
results is: R.A. = 0h54m50s.23, Decl. = +01:14:04.9 (J2000.0), which
is slightly (about 2") different from the value by da Costa, Noel and
Price (GCN 2765).
This message may be cited.
GCN Circular 2780
Subject
GRB041006 (= H3570): Chandra Observations In Progress
Date
2004-10-07T13:44:41Z (21 years ago)
From
George Ricker at MIT <grr@space.mit.edu>
GRB041006 (= H3570): Chandra Observations In Progress
G. Ricker, N. Butler, P. Ford, H. Marshall, R. Vanderspek (MIT); G.
Garmire (PSU); and D. Lamb (U. Chicago), on behalf of a Chandra GRB
ToO Team,
write:
Chandra grating spectrometer observations of the afterglow
counterpart (Da Costa, Noel, and Price; GCN2765) for GRB041006 -- a
bright, X-ray rich gamma-ray burst discovered by HETE (= H3570:
Galassi et al, GCN 2770) -- are in progress.
The Chandra LETG/ACIS observation commenced at approximately 5:30 UT
on 7 October 2004, and will continue for approximately 26 hours. The
scheduling of contemporaneous photometry and spectroscopy at other
wavelengths is strongly encouraged.
We are grateful to Harvey Tananbaum and the Chandra X-ray Center
observatory staff for scheduling this observation to commence only 17
hours after the GRB event.
This message may be cited.
GCN Circular 2779
Subject
GRB 041006 : optical observation at Bisei
Date
2004-10-07T10:14:19Z (21 years ago)
From
Hitoshi Yamaoka at Kyushu U., VSNET-GRB collab. <yamaoka@rc.kyushu-u.ac.jp>
K. Ayani (Bisei Astronomical Observatory (BAO)) and H. Yamaoka (Kyushu
Univ.) report:
We obtained R-band images of the optical afterglow (da Costa, Noel
and Price, GCN 2765) of GRB 041006 (Galassi et al., GCN 2770) with the
BAO 1.01-m reflector. The observation started on 16:44 UT. The
stacked image (mean epoch = Oct. 6.71 UT) shows the OT of which a
preliminary R magnitude is about 19.2, compared with the USNO A2.0 red
magnitudes.
This message may be cited.
GCN Circular 2778
Subject
GRB041006, optical I observation
Date
2004-10-07T07:57:05Z (21 years ago)
From
Karl Glazebrook at Johns Hopkins <kgb@pha.jhu.edu>
E. Hoversten, K. Chiu, E. Nissen, C. Kelleman, K. Glazebrook (Johns
Hopkins University, Baltimore, Maryland, USA)
We have observed a 7x11 arcminute field centered on the afterglow of
GRB041006 (GCN 2770) with the Morris Offit 20in Telescope of the Maryland
Space Grant Consortium. The telescope is located in downtown Baltimore,
Maryland and the observations were made with a student built CCD camera on
the night of 7 October 2004. Images were obtained in I band at midpoint
time 7 October 2004 UT 05:10:22, with a total exposure of 7200 seconds.
We do not detect an optical counterpart, and place an preliminary upper
limit on its magnitude at I=19.1 based on the faintest objects detectable
in the field. Aperture photometry was made with APPHOT in a 9 arcsecond
aperture, with relative photometry assuming I=16.1 (USNO-A2.0 red
magnitude 16.2) for the reference star at 00:54:38.09 +01:12:59.9.
Our image of the field may be viewed at
http://www.pha.jhu.edu/~chiu/JHUgrb.ps
More detailed analysis of data will follow. This message may be cited.
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
GCN Circular 2777
Subject
GRB041006 (=HETE3570): optical observations
Date
2004-10-07T03:03:23Z (21 years ago)
From
Patrizia Ferrero at IASF/CNR,Bologna <ferrero@bo.iasf.cnr.it>
P. Ferrero (IASF/CNR, Bologna; Osservatorio e Universita' di Teramo),
C. Bartolini, G. Greco, A. Guarnieri, A. Piccioni (Universita' di Bologna),
E. Mazzotti Epifani (INAF, Oss. di Capodimonte - Napoli), R. Gualandi
(INAF, Bologna Observatory) and G. Pizzichini (IASF/CNR, Bologna) report:
we observed the OT of GRB 041006 (=HETE3570) reported by Da Costa, Noel
and Price (GCN 2765).
By comparison with USNOA.2 star U0900_00213019, at R.A.= 00h 54m 43.41s
DEC.= +01d 15' 45.73", R mag=19.3 and USNOB.1 star 0912-0009780, at
R.A.= 00h 54m 43.38s DEC.= +01d 15' 45.38", I mag= 18.57 , we obtain:
mean UT filter exposure mag
Oct. 6.8393 Rc 900s 19.7
Oct. 6.8506 Rc 900s 19.7
Oct. 6.8637 Rc 900s 19.8
Oct. 6.8751 Ic 900s 19.35
Oct. 6.9627 Rc 4x900s 19.95
Magnitude errors are dominated by those on the magnitude of the
comparison star, probably ~ 0.3 mag in both filter (Monet et al. 2003,
ApJ 125, 984). The seeing was ~ 3".
Our images shall be available as soon as possible on a public directory
from where it will be possible to retrieve by sftp using the hostname:
ermione.bo.astro.it, username: publicGRB, password: GRB_bo and
directory: GRB041006.
This message may be cited.
GCN Circular 2776
Subject
ROTSE-IIIa Observations of GRB 041006
Date
2004-10-07T01:09:00Z (21 years ago)
From
Sarah Yost at U.Michigan <sayost@umich.edu>
Yost, S. A., Smith, D. A., Rykoff, E. S., and Swan, H. report on behalf of
the ROTSE collaboration:
Although ROTSE-IIIa (Siding Spring Observatory, Australia) was temporarily
off-line when the initial alert for GRB 041006 (HETE-2 3570, GCN Circ.
#2770) was distributed, ROTSE collaboration members reactivated the system
and manually initiated a standard ROTSE response sequence (10 5-s images,
10 20-s images, and then a large number of 60-s images) 16 minutes after
the time of the burst. The field was observed from Oct 6.52387 to 6.57424
(UTC). The observing plan was complicated by the receipt of a HETE-2
ground alert at Oct 6.558, which reset the sequence. ROTSE-III images are
unfiltered and calibrated against the USNO A2.0 catalog in R-band.
The optical counterpart discovered by Da Costa, Noel, and Price (GCN
Circ. #2765) is clearly visible. A preliminary analysis gives a
magnitude of 17.1+-0.4 in the first ROTSE-IIIa image. The magnitude
of the source clearly decays over the interval of the ROTSE-IIIa
observations, and we cannot detect it during the short-exposure
images taken after the receipt of the HETE-2 ground alert. We last
detect the source at a (preliminary) magnitude of 18.1+-0.4 in a 60-s
image taken beginning Oct 6.57263 (UTC). Three subsequent 60-s
exposures show no evidence for the source to upper limits around 18.1.
The decay is consistent with the same power-law reported by Price, Da
Costa, and Noel (GCN Circ. #2771).
This message may be cited.
GCN Circular 2775
Subject
GRB041006, optical observation
Date
2004-10-07T00:17:13Z (21 years ago)
From
Alexei Pozanenko at IKI, Moscow <apozanen@iki.rssi.ru>
B. Kahharov, I. Asfandiyarov, M. Ibrahimov, D. Sharapov (UBAI),
A.Pozanenko (IKI),
V.Rumyantsev (CrAO), G.Beskin (SAO) report:
We have observed the filed of error box of GRB041006 (HETE #3570, M.
Galassi, et al. GCN 2770) starting Oct.6 15:49 (UT) with 1.5m telescope of
Mt.Maidanak High-altitude Observatory. Several BVRI images were taken
between 15:49 and 16:51. We confirm a fading source found by G. Da Costa et
al. (GCN 2765). Preliminary reduction of the data against the USNO-A2.0
catalog yield the following OT magnitudes in R
UT exposure mag err
15:49 180 s 18.7 (0.09)
16:46 300 s 19.1 (0.10)
The magnitudes assume a temporal decay index about 1.5 which is stepper than
found by P.A. Price, et al. (GCN 2771) and may indicate a brake of a light
curve of the OT.
This message may be cited.
GCN Circular 2774
Subject
GRB041006, submillimetre observations
Date
2004-10-06T23:32:47Z (21 years ago)
From
Vicki Barnard at Joint Astro.Centre,Hawaii <vbarnard@jach.hawaii.edu>
V. Barnard, G. Schieven, R. Tilanus, J. Cox (all Joint Astronomy Centre),
J-F. Lestrade (Observatoire de Paris) report on behalf of the JCMT
afterglow collaboration:
We observed the afterglow position of GRB 041006 reported in GCN 2765 with
SCUBA on the James Clerk Maxwell Telescope on Mauna Kea, beginning at
14:29:50 UT on 06/10/04. In reasonable weather we obtained a flux density
at 850 microns of (2.93 +- 5.76) mJy. We were unable to observe further
as the source set.
Further observations are planned for 07/10/04 UT.
GCN Circular 2773
Subject
GRB041006: MASTER optical observations
Date
2004-10-06T20:43:40Z (21 years ago)
From
Vladimir Lipunov at Moscow State U/Krylov Obs <gcncirc@observ.inetcomm.ru>
V. Lipunov, A.Krylov, V.Kornilov, G.Borisov, D.Kuvshinov, A.Belinski,
M.Kuznetsov, S.Potanin, G.Antipov, E.Gorbovskoy, N.Tyurina
Sternberg Astronomical Institute, Alexandr Krylov Observatory, Moscow
At 4h 30m after HETE GRB trigger time (alert 3570) MASTER robotic
telescope (http://observ.pereplet.ru) had imaging the corresponding area
of the sky under the large zenit distance and bad weather conditions.
The first image was started at 16h53m UT.
We have 50 unfiltered images of the error box (45s exposition, 40 x 50
arcmin, 200 mm camera).
There is no optical transient up to 18.4 m at position da Costa et al.
(GCN2765).
Sum FITS image are available at
http://observ.pereplet.ru/images/GRB041006/
This message may be cited.
PS. Our wide-field camera (355mm) with AP16e CCD-camera are upgrading. So
last 5 circulars ( GCN >=2659) based on observations on small telescope.
GCN Circular 2772
Subject
GRB041006,optical observation
Date
2004-10-06T19:58:10Z (21 years ago)
From
Shouta Maeno at U.of Miyazaki <shouta@astro.miyazaki-u.ac.jp>
S.Maeno,E.sonoda,Y.Matsuo,M.Yamauchi
(University of Miyazaki)
"We have observed the field covering the error box of
GRB041006(HETE trigger 3570 trigger time 12:18:08UT) with
the unfiltered CCD camera on the 30-cm telescope at University
of Miyazaki.
The observation was started at 12:21:59 UT on Aug.6.
Observed field of view is 43 arcmin centered on R.A.=00h 55m 35.23s
Dec=+01d 13' 33.4".
The preliminary magnitude of new source is about 16.8mag. compared
with the USNO-A2.0 catalog.
The new source locates in the same position reported by G.da Costa et al.
(GCN2765)"
GCN Circular 2771
Subject
GRB 041006: Optical decay
Date
2004-10-06T15:25:44Z (21 years ago)
From
Paul Price at IfA,UH <price@ifa.hawaii.edu>
P.A. Price (IfA, UH), G. Da Costa (MSO) and N. Noel (IAC) report:
Preliminary analysis of six V-band frames from the SSO 40-inch from Oct
6.54 UT (t_GRB + 35 min) to 6.59 UT (t_GRB + 120 min) reveal that the
afterglow has a temporal decay index of alpha ~ 0.7 over these
observations, with an estimated magnitude of R ~ 18.5 mag at Oct 6.59
UT.
Assuming this decay holds, this predicts the GRB should be roughly R ~
20 mag at local midnight, US Eastern daylight savings time (UTC-4h).
The afterglow is also detected in the B band.
This message may be cited.
[GCN OPS NOTE (16:00 UT 06oct04): "da Costa" was changed to "Da Costa".]
GCN Circular 2770
Subject
GRB 041006 (=H3570): An X-Ray Rich GRB Localized in Real Time by HETE
Date
2004-10-06T15:09:31Z (21 years ago)
From
Roland Vanderspek at MIT <roland@space.mit.edu>
M. Galassi, G. Ricker, J-L. Atteia, N. Kawai, D. Lamb, and S. Woosley,
on behalf of the HETE Science Team;
T. Donaghy, E. Fenimore, C. Graziani, M. Matsuoka, Y. Nakagawa,
T. Sakamoto, R. Sato, Y. Shirasaki, M. Suzuki, T. Tamagawa, Y. Urata,
T. Yamazaki, Y. Yamamoto, and A. Yoshida, on behalf of the HETE WXM
Team;
N. Butler, G. Crew, J. Doty, A. Dullighan, G. Prigozhin, R. Vanderspek,
J. Villasenor, J. G. Jernigan, A. Levine, G. Azzibrouck, J. Braga,
R. Manchanda, and G. Pizzichini, on behalf of the HETE Operations and
HETE Optical-SXC Teams;
C. Barraud, M. Boer, J-F Olive, J-P Dezalay, and K. Hurley, on behalf
of the HETE FREGATE Team;
report:
The HETE Fregate and WXM instruments detected GRB 041006 (=H3570) at
12:18:08 UT (44288 SOD) on 06 October 2004. The WXM flight software
localized the burst in real time, resulting in a GCN Notice 42 seconds
after the burst trigger. The flight error region was a circle of
14 arcminutes radius (90% confidence) centered at
RA = 00h 54m 54s, DEC = +01d 18' 37" (J2000).
Ground analyses of the burst data allow the error region to be refined
to a circle of 5.0 arcminutes radius (90% confidence) centered at
RA = 00h 54m 53s, DEC = +01d 12' 04" (J2000).
Preliminary spectral analyses show the 2-30 keV fluence of GRB 041006 to
be 5e-6 erg/cm2 and the 30-400 keV fluence to be 7e-6 erg/cm2: the
classification for GRB 041006 is, therefore, "X-ray rich GRB".
GRB 041006 is very similar to GRB 030329 in its lightcurve shape and
spectral characteristics, although it is 20x fainter than GRB 030329.
GRB 041006 shows a soft precursor before the main gamma-ray pulse. The
empirical redshift indicator for this burst is 0.4; for GRB 030329, it
was 0.2.
This message may be cited.
GCN Circular 2768
Subject
GRB041006: Fading of optical afterglow candidate
Date
2004-10-06T14:37:27Z (21 years ago)
From
Derek Fox at CIT <derekfox@astro.caltech.edu>
D.B. Fox (Caltech) reports on behalf of a larger collaboration:
"We have imaged the optical afterglow candidate of Costa, Noel & Price
(GCN 2765) with the Robotic P60 on two occasions in the I-band, at
mean epochs 12:32:07 UT and 12:41:36 UT. We can confirm that the
candidate is stationary, and faded by approximately 0.45 +/- 0.15 mag
in I over this interval by comparison to several nearby stars in the
field."
GCN Circular 2767
Subject
GRB 041006 : Optical follow-up observation at KISO
Date
2004-10-06T14:21:15Z (21 years ago)
From
Yuji Urata at RIKEN <urata@crab.riken.go.jp>
H. Fukushi(Tokyo Univ.), M. Isogai(Tokyo Univ.), and Y. Urata(RIKEN)
" We have detected the candidate reported by G. da Costa et al. (GCN
2765) in R-band at Kiso observatory. The brightness at about 55 min
after the burst is R~17 compared with USNO-A2.0 stars."
This message may be cited.
GCN Circular 2766
Subject
GRB 041006: Finding chart
Date
2004-10-06T14:05:14Z (21 years ago)
From
Paul Price at IfA,UH <price@ifa.hawaii.edu>
P.A. Price (IfA, UH), G. Da Costa (MSO) and N. Noel (IAC) report:
We have produced a finding chart of the optical afterglow candidate
reported in GCN #2765, which is available from
http://www.ifa.hawaii.edu/~price/grb041006.ps
The offset from the star marked is 46.95" East and 15.02" North.
We estimate that the optical afterglow was 17th magnitude in our image.
Observers with spectroscopy resources are encouraged to observe the
source.
P.
[GCN OPS NOTE (16:00 UT 06oct04): "da Costa" was changed to "Da Costa".]
GCN Circular 2765
Subject
GRB 041006: Optical afterglow candidate
Date
2004-10-06T13:41:44Z (21 years ago)
From
Paul Price at IfA,UH <price@ifa.hawaii.edu>
G. Da Costa (Mount Stromlo Observatory), N. Noel (IAC) and P.A. Price
(IfA, UH) report:
We have observed the error circle of GRB 041006 (HETE #3570) with the
Wide Field Imager on the SSO 40-inch telescope. Inspected exposures at
this time consist of a single 300 sec integration in V-band at 2004 Oct
6.54 UT. Comparison with the DSS yields an optical afterglow candidate
at the coordinates:
00:54:50.17 +01:14:07.0 J2000
Further results will follow.
This message may be cited.
[GCN OPS NOTE (16:00 UT 06oct04): "da Costa" was changed to "Da Costa".]