GRB 980329

S. Klose, H. Meusinger & H. Lehmann (Thueringer Landessternwarte Tautenburg,
Germany) report:

The error box of GRB 980329 was imaged in V, R & I on March 29.8 - 30.0 UT, 
and in R and I on March 31.8 - 31.9 UT, using the Tautenburg Schmidt 
telescope equipped with the Schmidt focus CCD camera.  Further R-band images 
were obtained on March 31.8 UT with the 2.2-m telescope at Calar Alto, Spain,
equipped with CAFOS. 

A comparison of these images shows no object in the final 1-arcmin GRB error
box for which the R-magnitude has declined by more than about 0.5 mag.
Based on this finding it seems that the magnitude of the GRB afterglow
was R > 20 about 15 hours after the burst (or the magnitude of the optical
afterglow did not notably vary over this time span). 

R-band images (gif-files) taken on March 29.85 and 30.0 UT are available
via anonymous ftp from 

    ftp.tls-tautenburg.de

in the directory /pub/klose. 
Further images will be make available, when deeper I-band images are obtained. 

Comments are welcome.

A. Guarnieri, C. Bartolini, A. Piccioni, Universita' di Bologna, G. Clementini 
and G. Valentini, Osservatorio Astronomico di Bologna;
A. Castro-Tirado and Javier Gorosabel, Laboratorio de Astrofisica Espacial y
                                 Fisica Fundamental (LAEFF-INTA, Madrid);
A. Pedrosa, Centro de Astrofisica da Universidade do Porto;
M.R. Zapatero-Osorio, A. Alonso, Instituto de Astrofisica de Canarias, IAC, 
                                 Tenerife;
J. Greiner, Astrophysikalisches Institut Potsdam;
E. Costa, Istituto di Astrofisica Spaziale, Frascati,
                                 on behalf of the BeppoSAX team;

report:

R-band images containing the error box for 1SAX J0702.6+3850 (IAUC 6854)
were obtained on Mar 29.79 and 30.81 at the 1.52-m telescope at Bologna 
Observatory, on Mar 29.90, 30.91 and 31.95 at the 1.0-m Jacobus Kapteyn 
Telescope at La Palma, Canary Islands, and on Mar 31.02 and 31.92 at the OAN 
1.52-m telescope at the German-Spanish Calar Alto Observatory.  No variable 
object is found down to R = 22.  Any variation was smaller than 0.3.
Observations at other wavelenghts, especially infrared, are encouraged.

GRB 980329 optical observations:

S. G. Djorgovski, S. R. Kulkarni (Caltech), J. Tonry, A. Barger, E. Fulton
(U. Hawaii), R. Gal, J. Sievers, and K. Adelberger (Caltech), on behalf of 
the Caltech GRB collaboration, report:

We obtained CCD images of the field of the proposed x-ray counterpart
of GRB 980329 (IUC 6854), using the University of Hawaii 88-inch telescope
at Mauna Kea, on UT 1998 March 30 and 31 (about 1 and 2 days after the
burst).  R band images taken on UT March 30 have a limiting magnitude
of R ~ 22.3, and images taken on March 31 have a limiting magnitude of
R ~ 23.0.  Additional B and V band images were also obtained on March 31. 

No significantly variable objects have been found in these data.  Moreover, 
there were no objects in these CCD images which are not also present in the 
digital version of POSS-II (DPOSS), which reach about 1 to 1.5 magnitudes 
deeper than the publicly available DSS (POSS-I) images, above the limit of 
the photographic survey.

The (stellar) object mentioned by Ilovaisky and Chevalier (IAUC 6856) is
detected in DPOSS red images, and CCD images, and it does not vary.  It
is most likely a foreground Galactic star.

There is a very blue stellar object outside the SAX error circle, and thus
probably unrelated to the GRB, at RA = 07:02:42.66  DEC= +38:49:15.8 (J2000).

Additional, much deeper R and I band images of the field, with a limiting
magnitude of R ~ 27, were obtained at the WMKO Keck-II 10-m telescope on 
UT April 02.  Again, there are no significantly variable objects present 
within the limits of the earlier (March 30 and 31) CCD data.  Further 
observations of the field with the Keck telescope are in progress.

These images are shown at http://astro.caltech.edu/~george/grb/grb980329.html

This note can be cited.

J. M. Quashnock, D. E. Vanden Berk, D. M. Cole, A. R. Cooray,
D. Q. Lamb, F. J. Castander, K. Gloria, and D. Long,
University of Chicago, on behalf of the
Astrophysical Research Consortium (ARC), report:
"Between Apr. 1.167 UT and Apr. 1.277, we made near-infrared observations
of a region of the sky that includes the entire SAX NFI error box 
for GRB 980329 (IAUC 6853, 6854), using the GRIM II instrument 
mounted on the ARC 3.5-m telescope at Apache Point Observatory.
At the epoch Apr. 1.167-1.177 and at a position R.A. = 7h02m38s.7, 
Decl.= +38o50'27" (J2000.0) consistent with that of the R=20.6 object 
reported in IAUC 6856, we find an object of magnitude J = 17.7 +/- 0.1.
This object is approximately 6.4" South and 3.0" West of the bright
R=15.8 star reported in IAUC 6856, for which we measure J = 13.9 +/- 0.1.
At the epoch Apr. 1.267-1.277 (approximately 2.5 hours later),
we find no measurable change (less than approximately 0.1 mag)
in the J magnitude of the object."

This report is citable.

G.B. Taylor, D.A. Frail (NRAO), S.R. Kulkarni (Caltech), and
the BeppoSAX GRB team report:

We have observed the field containing the proposed x-ray counterpart
1SAX J0702.6+3850 of GRB 980329 (IAUC 6854) with the VLA at 8.4 GHz
on UT 1998 Mar 30.2, April 1.1, and April 2.1.  Observations on April
1.1 detected a radio source VLA J0702+3850 within the 1 arcminute
error circle of 1SAX J0702.6+3850.  The coordinates of
VLA J0702+3850 are: ra = 07h02m38.02170s dec = 38d50'44.0170" (equinox
J2000) with an uncertainty of 0.05 arcsec in each coordinate.  The
size of this radio source is less than 0.25 arcsec.  The density of
sources on the sky stronger than 250 microJy at this frequency is
0.0145 arcmin**-2.

The flux density measurements of VLA J0702+3850 are as follows:

Date(UT)   8.4 GHz Flux Density
--------   ----------------------
Mar 30.2   166 +/- 50 microJy
Apr  1.1   248 +/- 16    "
Apr  2.1    65 +/- 25    "

where the uncertainty in the measurement reflects the 1 sigma rms
noise in the image.  These measurements clearly demonstrate that
the radio source is variable on timescales of less than 1 day.
This rapid variability is similar to that observed in the 
radio afterglow from GRB 970508.  We propose VLA J0702+3850
is the radio afterglow from GRB 980329.

Additional radio observations are in progress.

This note is citable in publications.

S. G. Djorgovski, S. R. Kulkarni, J. Sievers (Caltech), D. Frail and 
G. Taylor (NRAO), on behalf of the Caltech-NRAO GRB collaboration, report:

We have detected a galaxy coincident to within the astrometric errors (about
0.5 arcsec) with the variable radio source detected at the VLA by Taylor et al.
(see GCNC#40) on deep R-band images taken with the Keck-II 10-m telescope
on 02 April 1998 UT.  The galaxy has a magnitude R = 25.7 +- 0.3 (preliminary
reductions).  The image of the field is shown at
http://astro.caltech.edu/~george/grb/grb980329.html.

We propose that this is the host galaxy of the radio transient detected at the
VLA, which may be the afterglow of GRB 980329.

Further observations of this field are in progress.

This note can be cited.

Sylvio Klose, Thueringer Landessternwarte Tautenburg, Germany, reports:

I-Band images obtained on March on March 29.8-30.0 UT, using the
Tautenburg Schmidt telescope equipped with the Schmidt focus CCD camera
show an object at the position of the radio source reported by
Taylor et al. [GCN Circ #40].

This object was not visible on the I-band images taken on March 31.8-31.9 UT
with the Tautenburg telescope (GCN #36
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 ).  It was also not found on an I-band
image taken on April 1.85 UT by H. Lehmann and H. Meusinger, Thueringer
Landessternwarte, with the Calar Alto 2.2-m telescope equipped with CAFOS.

Since no R-band counterpart was seen on the Tautenburg images taken on
March 29.8-30.0 UT, I hesitate to claim the detection of this source. 
This object is visible on various I-band frames, and also appears
if flat-fielding is not performed.  Its magnitude is about I=20,
but I do not have a photometric standard.

These Tautenburg I-band Images are availabe via anonymous ftp from 
    ftp.tls-tautenburg.de
in the directory /pub/klose.

Comments are welcome.

J. Larkin, A. Ghez (UCLA) in collaboration with S. Kulkarni,
S. Djorgovski (Caltech), D. Frail, and G. Taylor (NRAO) report:

We have detected a near infrared counterpart to the variable radio
source detected at the VLA by Taylor et al. (see GCNC#40),
the R-band source reported by Djorgovski et al. (see GCNC#41), and
the possible I-band transient reported by Klose (GCNC#43).  Preliminary
analysis of observations obtained on UT 1998 April 02 and April 03 at
the Keck-I 10-m telescope reveal a K = 21.0 mag source that does not
show strong variations (delta K < 0.5 mag).  The infrared, optical and radio
positions all agree to within the astrometric uncertainties of about 
0.5 arcsecond.

We suggest that a possible explanation for the relatively red color
of the host galaxy (R-K = 4.7 mag) and the lack of optical transient 
detections may be dust obscuration.

This note can be cited.

R-band observations of the GRB980329 error box were obtained with the 
3.5 m WIYN telescope on Kitt Peak on UT 1998 April 1.17 and April 3.10.  
The position of the radio transient (see GCNC #40) was empty to limits of 
24.2 and 23.9 mag respectively.

F. Mannucci, M. Salvati, P. Tozzi, Osservatorio Astrofisico di Arcetri,
Firenze, Italy, M. Di Martino, Osservatorio Astronomico di Torino, Italy,
E. Palazzi and E. Pian, Istituto di Tecnologie e Studio delle Radiazioni
Extraterrestri, CNR, Bologna, Italy, on behalf of a large collaboration

report: 

On March 29.84-29.86 UT, the SAX-WFC error box of GRB980329 (IAUC 6853)
was imaged at the Gornergrat Infrared Telescope (TIRGO) with ARNICA + J
band filter.  A preliminary analysis of the data shows that the galaxy
reported by Djorgovski et al. (GCNC #41) is detected at 2-sigma
significance with a magnitude J = 19.2 (+0.8,-0.5 at 1 sigma).

D. M. Cole, A. R. Cooray, J. M. Quashnock, D. E. Vanden Berk,
D. Q. Lamb, D. E. Reichart, G. T. Richards, K. Gloria, D. Long, and
T. Hoyes, University of Chicago, on behalf of the
Astrophysical Research Consortium (ARC), report:

"We made near-infrared observations (GCN #39
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 , IAUC 6860)
of the SAX NFI error box for GRB 980329 (IAUC 6853, 6854)  
between Apr. 1.167 UT and Apr. 1.277 UT, using the GRIM II instrument 
mounted on the ARC 3.5-m telescope at Apache Point Observatory.
We find no detectable object, down to a limiting J magnitude of 20.9 +/- 0.5
(1 sigma) at the position R.A. = 7h02m38s.02, Decl. = +38o50'44" (J2000.0) of
the variable radio source VLA J0702+3850 proposed by Taylor et al. (GCN #40
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 ) 
to be the radio afterglow from GRB 980329. The measurement by Mannuci et al. 
(GCN #46
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 ) of a magnitude J = 19.2 (+0.8,-0.5) object at the position
of the radio source at epoch Mar. 29.84-29.86 UT implies
that this object dimmed by J magnitude 1.7 +/- 0.9 
during a period of approximately 2.4 days."

This report is citable.

E. Palazzi, N. Masetti, E. Pian, F. Frontera (ITeSRE-CNR, Bologna), L. 
Nicastro (IFCAI-CNR, Palermo), P. Vreeswijk, T. Galama, P. Groot, J. van
Paradijs (U. Amsterdam), M. Della Valle (Oss.  Astr. Padova), E.  Costa,
M. Feroci, L. Piro (IAS-CNR, Rome), C. Kouveliotou (MSFC-NASA), and
C. Lidman (ESO) 

report: 

The error box of GRB980329 (IAUC 6853) was observed with the NTT at ESO
(La Silla, Chile) on March 29.99, 30.99 and April 1.01 UT with EMMI in R
and V band filters.  Observations lasted 10+10 minutes per filter per
night.  Limiting magnitudes were ~24.0 in R and 23 in V.  On March 29.99,
at the position RA = 07h02m38s, Dec = +38deg50'44".1 (J2000), coincident
(to within the astrometric errors) with VLA J0702+3850 (GCN #40
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 ) and with
the galaxy reported by Djorgovski et al. (GCN #41
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 ), we detect an R = 23.5
(+/- 0.2) object.  The source is not detected in V, and in the subsequent
nights is undetected in both bands.  Using R = 25.7 (April 2, Djorgovski
et al., GCN #41
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 ) we obtain a luminosity power-law decay index <~ -1.3.
The extrapolation of this power-law to the time of the observations reported
by Guarnieri et al. (GCN #37
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 , Mar 29.79), Brocato et al. and Cappellaro
(see below) is consistent with their non-detections.  The NTT R band images
can be found at the Web site
http://www.tesre.bo.cnr.it/~nicastro/grb980329, as well as the TIRGO
J band images reported in GCN #46
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 . 

In addition:

E. Brocato, A. Piersimoni, and G. Raimondo (Oss. Astr. Teramo) report: 
We imaged the GRB980329 error circle with the 0.72-m telescope at Campo
Imperatore (Teramo) equipped with a Tek-CCD and R band filter on March
29.83 UT for 1800 s.  No object brighter than R = 20 is detected at the
VLA source position. 

E. Cappellaro (Oss. Astr. Padova) reports:  On March 29.81 and 29.99 UT,
the GRB980329 error circle was imaged for 1500 s using the 1.8-m telescope
at the Asiago observatory with AFOSC and R band filter.  Down to a limiting
magnitude of R = 21, no object is found at the VLA source position.

K. Hurley (UCB) on behalf of the Ulysses GRB team,
M. Feroci (IAS/CNR, Rome) and F. Frontera (ITESRE/CNR, Bologna) 
on behalf of the BeppoSAX/GRBM Team report:

We have derived a preliminary IPN annulus for this burst using
Ulysses and the BeppoSAX Gamma-Ray Burst Monitor.  The annulus
is described by a circle of radius of 49.898 degrees centered at
RA(2000) = 154.298 degrees, Declination (2000) = 13.169 degrees.
The half-width of the annulus is 0.022 degrees. The annulus
intersects the WFC error circle (IAUC 6853) and reduces its area.  
The intersection points are:

		RA(2000)		Decl (2000)
     105.628 o = 7 H 2 M 30 S      38.808 o = 38 o 48 ' 29 "
     105.662 o = 7 H 2 M 38 S      38.895 o = 38 o 53 ' 40 "
     105.683 o = 7 H 2 M 43 S      38.796 o = 38 o 47 ' 45 "
     105.716 o = 7 H 2 M 51 S      38.880 o = 38 o 52 ' 49 "

This error box includes the SAX NFI X-ray source (IAUC 6854), radio
source (GCN #40
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 ) and the optical transient (GCN #48
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 ).  Further processing 
will reduce the annulus width.  An image may be found at
http://ssl.berkeley.edu/ipn3/980329/.

I. A. Smith (Rice University) and R. P. J. Tilanus (Joint Astronomy Centre) 
report on behalf of the James Clerk Maxwell Telescope (JCMT) GRB collaboration:
 
We used the SCUBA sub-millimeter continuum bolometer array on the JCMT to 
observe the variable radio source VLA J0702+3850 proposed by Taylor et al. 
(GCN #40
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 ) as the radio afterglow to GRB 980329.
 
On UT 1998 April 5.2 we detected a source at 850 microns with a preliminary 
flux density of 5 +/- 1.5 mJy.  This source was confirmed on April 6.2 with 
a flux density of 4 +/- 1.2 mJy, resulting in an average of 4.5 +/- 1 mJy 
over the two days.  The 850 micron source is present in all our separate 
integrations making us confident it is real.  A hint of a fading trend 
appears to be confirmed by observations on April 7.2 when the (preliminary)
850 micron flux density was 2 +/- 0.8 mJy. 

The source was not detected at 450 microns with a preliminary rms of 10.0 
mJy averaged over the first two days.

Assuming these fluxes are due to the burst counterpart, they should represent
"clean" measures of its intensity, unaffected by scintillation and extinction.  
Monitoring with SCUBA is continuing.

We wish to thank Dr. L. Avery and Dr. J. MacLeod for their cooperation and
valuable help in obtaining these observations, and Dr. G. Watt and Dr. I. 
Robson for rapidly scheduling the observations.

This report may be cited in publications.

J. Larkin and A. Ghez (UCLA) in collaboration with S. Kulkarni,
S. Djorgovsk (Caltech), D. Frail and G. Taylor (NRAO) report:

We have fully reduced our K-band images of the field surrounding the
gamma ray burst GRB980329.  We confirm our earlier strong detection of
a compact (<0.6'' FWHM) object at the radio coordinates reported by
Taylor et al. (see GCN#40
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 ) and coincident with the optical counterpart
announced by Djorgovski et al. (see GCN#41
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 ).  The observations include
two separate 90 minute exposures at the Keck 10 meter telescope
obtained on UT 1998 April 02 and April 03, respectively.  The total
K-band magnitudes of the object are 20.7+-0.2 mag on April 02, and
20.9+-0.2 mag on April 03.  The source is unresolved in our images,
even if we include only those frames taken under the best seeing
conditions of 0.5 to 0.6 arcseconds.

The final K band image can be found at
	http://www.astro.ucla.edu/~larkin/grb.html

This note is citable.

H.Pedersen (Copenhagen University Observatory), 
J.Fynbo (Institute of Physics and Astronomy, Aarhus),
E.Valtaoja (Tuorla Observatory, Turku), 
M.Tornikoski (Metsahovi Radio Observatory, Helsinki),
J.Clasen (Nordic Optical Telescope, La Palma), and
E.Palazzi (Istituto TeSRE, Bologna), report:

Using the 2.56 m Nordic Optical Telescope, La Palma, 
we have obtained a total of seven 600 s R band exposures
of the proposed host galaxy (ref. GCN #41
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 , #51
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 ). 

The exposures were taken March 30.924 - 30.942 (2 exp.), 
March 31.866 - 31.882 (2 exp.), and April 01.879 - 02.029 (3 exp.). 
One 300 s I band exposure was obtained on March 31.919.

The optical transient is not clearly detected in any single
exposure, nor in the sum of exposures from any night.  However, 
the sum of all R exposures shows a very faint object at the 
cited position for which we derive m(R) = 24.8 +/- 0.5
(using the R=15.8 object from IAU Circ. No. 6856 as calibration). 

The data files can be retrieved from 

http://www.astro.ku.dk/~holger/g/IMAGES/GRB980329/NOT_R.fits.gz
                                              .../NOT_I.fits.gz

Further to this, H.Pedersen reports:

Using the 45/77 cm Brorfelde Schmidt, a series of seventeen 
500 s R band exposures were obtained March 29.860 - 29.973. 

None of these exposures shows any object at the position of
the optical counterpart.  During the observing interval, the 
detection limit deteriorated gradually, from R=18.5 to 18.0 

K.Augustesen kindly performed the Schmidt observations.

This message can be cited.

M.R. Metzger (Caltech) reports:

Near-infrared K-band images of the area surrounding the variable radio source
detected by Taylor et al. (GCNC #40), possibly associated with GRB 980329
(IAUC 6853, 6854), were obtained on Apr 6.27 and Apr 8.28 with the Keck-I
10m telescope.  The source reported by Larkin et al. (GCNC #51, coincident
with the galaxy reported by Djorgovski et al., GCNC #41) was detected on
both nights, at K=21.4 +/- 0.2 mag (6.27) and K = 21.9 +- 0.4 mag (8.28).
Comparison with the magnitudes reported by Larkin et al. indicates that the
source has faded by about 1 mag between Apr 2.3 and Apr 8.28.  This suggests
that part of the K flux may be IR afterglow of GRB 980329.  It is consistent
with fading, detections, and upper limits reported previously (GCNC #41,
#46, #48, IAUC 6864, 6866, 6868).  Further measurements are suggested to
estimate the IR brightness of any underlying host.

------------

Mark R. Metzger, mrm@astro.caltech.edu
Caltech 105-24
Pasadena, CA  91125



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J. Greiner (AI Potsdam, Germany), W. Voges (MPE Garching) and F. Frontera
(Bologna, Italy), E. Costa and L. Piro (IAS Rome, Italy) report:

A ROSAT target-of-opportunity observation was performed towards the position 
of GRB 980329 (IAUC 6853) between April 1--3, 1998. The total exposure time
was 33.5 ksec. No X-ray source is detected within the WFC error box at
the 3 sigma significance level or higher (upper limit of 0.0001 cts/s). 
Adopting a power law spectrum with photon index of 2.0 and only galactic 
absorption (9*10^20 cm^-2), this corresponds to a flux limit of
9.3E-15 erg/cm^2/s in the 0.1-2.4 keV band. The non-detection of the 
X-ray afterglow source 1SAX J0702.6+3850 as detected with the BeppoSAX NFI 
(IAUC 6854) implies that the X-ray flux of the GRB 980329 afterglow decayed 
according to t^-1.8 or steeper.

An image of the ROSAT observation is available at 
http://www.obs.aip.de/~jcg/grb980329.html.

James Rhoads, Arjun Dey, Buell Jannuzi, and Megan Sosey (on behalf of
the KPNO GRB followup team); Sylvio Klose; Daniel Reichart; Andrew
Fruchter; and Francisco Castander report:
 
We have used data obtained by Rhoads on the night of 980403 UT to
calibrate Klose's I band measurement of the optical transient
associated with GRB 980329 (GCNC #43).  We find an optical transient
magnitude I=20.8 +- 0.3 on March 29.8-30.0 (cf. Reichart et al, in
preparation).  The corresponding flux density is 11 +- 3 microJansky.
The data consisted of 1200 seconds integration per filter on the GRB
980329 field in R band (April 3.147) and I band (April 3.167) at
airmass 1.1, plus brief R and I band observations of the SA107 field
at airmass 1.4.  The data were taken with the 4 meter Mayall telescope
and Mosaic CCD Imager at Kitt Peak National Observatory.  Weather was
photometric with poor image quality (from 1.25 to 1.75 arcsec).
Details of the photometric calibration and a table of reference star
magnitudes in the GRB 980329 field are at the end of this circular.

We used the same data to measure the flux at the location of the
transient.  No obvious source is present at the location of the
transient (7:02:38.0 +38:50:44 J2000.0) in either filter.  R band
photometry using a 0.75 and 1.25 arcsecond radius apertures, corrected
for aperture losses using the curve of growth, yield flux estimates
of 0.40 +- 0.25 and 0.80 +- 0.25 microJansky, where the error bar
includes contributions from photon counting noise and from sky
subtraction uncertainties only.  Conservatively, this gives a 3 sigma
upper limit of 1.50 microJansky (for a one-sided confidence interval
with probability 99.73%) and R > 23.3 magnitudes.

For the I band, the aperture-corrected point source fluxes measured in 
0.75 and 1.25 arcsecond radius apertures are 0.06 +- 0.51 and -0.12 +- 0.44
microJansky.  The first implies a 3 sigma upper limit of 1.48 microJansky
and to I > 23.0, while the second gives an upper limit of 1.10 microJansky
and I > 23.3 magnitudes.

In addition, we report a K band upper limit using data obtained by
Dey, Jannuzi, and Sosey (on behalf of the NOAO Deep Widefield Survey
team) on 1998 April 3.205 using the Kitt Peak National Observatory 2.1
meter telescope and ONIS camera.  No point source is apparent at the
location of the transient.  The RMS counts in the image imply a 3
sigma upper limit of 13.4 microJansky for a point source (in a 1
arcsec radius aperture and corrected using the curve of growth),
which corresponds to K > 19.2 at the 3 sigma level.

 - Details of the photometric calibrations - 
Reliable optical fluxes were measured for the Landolt standard stars
SA107-212, 213, 357, 359, 351, 457, 456, 600, 599, 612, 626, and 627.
Standard star and GRB field photometry was done in a similar fashion,
with growth curves derived from multiaperture photometry used to
correct all magnitudes to an effective 7" radius.  The photometric
errors in the GRB frame were taken from the IRAF "mkapfile" task,
which applies the aperture corrections.  Additional errors were added
in quadrature to account for uncertainties in the photometric zero
point (+- 0.004 mag in both R and I), color correction terms (+-
0.07*[R-I - 0.42]), and airmass correction term (+- 0.01 mag for I
band and +- 0.024 mag for R band).
 
The table of measured magnitudes for objects near GRB 980329:
# RA (J2000) Dec        R     err(R)      I    err(I)
#
7:02:39.0 38:50:32.7  15.7     1.0      15.300  0.2 
7:02:37.5 38:50:33.5  15.85    1.0      15.450  0.12
7:02:35.1 38:50:23.2  16.30    0.3      15.988  0.036 
7:02:40.1 38:50:11.8  16.9664  0.0314   16.647  0.0155
7:02:39.4 38:50:03.1  18.4428  0.0275   18.093  0.0175
7:02:38.7 38:50:26.9  20.655   0.0646   19.473  0.0623
7:02:36.6 38:50:36.3  20.3862  0.0536   19.331  0.0478
7:02:36.3 38:50:19.8  20.5135  0.0464   19.625  0.0459 
7:02:38.4 38:50:50.7  21.2876  0.0688   20.026  0.0711 
7:02:51.0 38:49:31.0  17.6592  0.0456   16.668  0.0399 
7:02:50.4 38:49:57.1  17.9663  0.0258   17.539  0.0161
#
Users of this table should be aware that the magnitude uncertainties
for the different stars include some sources of systematic error
(airmass and color terms) that are not independent from star to star.
Also, the first two entries are substantially saturated in R and I;
the third is substantially saturated in R and perhaps marginally in I;
and the fourth may be marginally saturated in R.  Photometric errors
quoted for saturated stars are approximate guesses.
 
More detail, and sections of the processed R and I band images, are
available from  http://www.noao.edu/noao/grb/980329.html .
This report is citable.

HST/STIS observations of the host galaxy of GRB 980329

Stephen Holland, Bjarne Thomsen (University of Aarhus),
Jens Hjorth, Johan Fynbo (University of Copenhagen),
Michael Andersen (University of Oulu),
Gunnlaugur Bjornsson (University of Iceland),
Andreas Jaunsen (ESO),
Priya Natarajan (University of Cambridge, & Yale), and
Nial Tanvir (University of Hertfordshire)

     We have used the Space Telescope Imaging Spectrograph (STIS) on
the Hubble Space Telescope to image the host galaxy of GRB 980329.  We
obtained 8072 seconds of STIS/CCD images with the 50CCD (clear)
aperture and 5416 seconds with the F28X50LP (long pass) aperture.
This data was taken as part of the Survey of the Host Galaxies of
Gamma-Ray Bursts (Holland et al., GCN 698
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 ) approximately 880 days
after the burst occurred.  Combined images are now available at
"http://www.ifa.au.dk/~hst/grb_hosts/data/index.html".  The drizzled
F28X50LP image is based on two orbits worth of data, and will be
updated when the data from the third orbit is available.

       A preliminary determination of the location of the radio
transient VLA J070238.0+385044 associated with GRB 980329 (Taylor et
al. 1998, ApJL, 502, L115), based on the astrometry of three USNO-A2.0
stars, is (X,Y) = (1039,1027) where the three-sigma uncertainty in the
astrometric solution is 20 drizzled STIS pixels (0.5 arcsec).  There
is a faint, extended object at (X,Y) = (1031,999) in our drizzled
50CCD image.  This object is also visible in the F28X50LP image.  The
object is approximately three sigma southwest of the position of the
GRB, and is the best candidate for the host galaxy of GRB 980329.  An
image showing the location of the galaxy and the GRB is available at
"http://www.ifa.au.dk/~hst/grb_hosts/data/grb980329cd.gif".  The
probable host galaxy has AB magnitudes, in an aperture of radius 0.25
arcsec, of CL = 28.6 +/- 0.3 and LP = 28.1 +/- 0.3.  If we assume that
the galaxy has a power-law spectrum then the preliminary Kron-Cousins
R-band magnitude is R = 27.7 +/- 0.3.  We also derived a preliminary
calibration based on two stars from Rhoads et al. (GCN 157
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 ) and found
R = 28.2 +/- 0.3.  These results are consistent with each other, and
are consistent with the host magnitude being 26.8 < R < 29, as
determined by Gorosabel et al. (1999, A&A, 347, L31) from the decay of
the optical light curve.  The faintness of the galaxy is consistent
with it having a redshift of z > 2 (Fruchter 1999, ApJ 512, L1; Lamb
et al. 1999, A&AS, 138, 479), although we can not rule out z < 2 from
the HST/STIS data alone.