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TITLE:   GCN GRB OBSERVATION REPORT
NUMBER:  644
SUBJECT: BeppoSAX GRB000424  
DATE:    00/04/25 16:37:39 GMT
FROM:    SAX Science Operations at IAS/CNR Frascati  <saxsci@ias.rm.cnr.it>

BeppoSAX GRB000424  


On April 24 at 18:18:07 UT a burst (GRB000424: BATSE trigger 8086)
was detected in WFC (2-26 keV). BeppoSAX GRBM was switched-off because of
proximity to SAGA.
The position is:
 
R.A.= 104.718
 
Decl.= 49.873
 
with an error radius of 2.5'.
 
A fast position distribution and a follow -up with BeppoSAX NFI could not
be performed because of the holiday period in Italy (see also GCN 634 and
BeppoSAX mail n.00/06).
 
 
L. Piro
BeppoSAX Mission Scientist

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TITLE:   GCN GRB OBSERVATION REPORT
NUMBER:  647
SUBJECT: GRB 000424, Optical Observations
DATE:    00/04/25 23:46:12 GMT
FROM:    Sergei Guziy at Astro.Obs. of Nikolaev State U.  <grb@aok.mk.ua>

S. Guziy, A. Shlyapnikov, Kalinenkov Astronomical Observatory
of Nikolaev University (Nikolaev),
and R. Hudec, Astronomical  Institute (Ondrejov),

report:

"We have obtained 6 images in the R band of the region for GRB000424
(GCN 644). The total integration time is 360 s (6x60s). These images
were taken on Apr. 25.86, i.e. 26-hr after the event, with the 0.7-m
telescope of the Astronomical Observatory of the Nikolaev University.
Comparison with the Digitized Sky Survey does not reveal any new
object brighter than about R = 18.1 within the BSAX WFC error box."

This message may be cited.

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TITLE:   GCN GRB OBSERVATION REPORT
NUMBER:  648
SUBJECT: GRB000424, optical observations
DATE:    00/04/26 09:01:15 GMT
FROM:    Fiona Harrison at CalTech  <fiona@srl.caltech.edu>

A. Dressler (Carnegie), A. Diercks, R. Gal, S. Yost, J. Bloom, and
F. Harrison (Caltech) report:

"We imaged the entire error circle of GRB000424 (Piro et al., GCN #644)
with the COSMIC instrument on the Palomar 200" telescope at April
26.12 UT.  Exposures consisted of 3x600s images in R-band with
approximately 1.3" seeing FWHM.  Visual comparison with a photographic
f-band (approximate R-band) image from the DPOSS survey reveals no new
objects to the detection limit of the plate (approximately R ~ 20.7)."

This message may be cited.

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TITLE:   GCN GRB OBSERVATION REPORT
NUMBER:  649
SUBJECT: GRB000424, optical observations
DATE:    00/04/26 16:35:01 GMT
FROM:    Rene Hudec at AIO  <rhudec@asu.cas.cz>

R. Hudec, L. Sarounova (Astronomical Institute Ondrejov), M. Tichy and
J. Ticha (Klet Observatory) report:

We have obtained 3 CCD images (unfiltered, V and R; the integration time
3 x 180 sec) with the 65 cm telescope of  the Ondrejov Observatory at
April 25.90 UT, and 12 unfiltered CCD frames (total integration time 780
sec) with the 57 cm telescope of  the Klet Observatory at April 25.95
UT. Each of the images covers the entire error circle of GRB000424 (Piro
et al., GCN #644). Comparison with the DSS  reveals no new objects
brighter than about mag V = 19.6 within the BeppoSAX WFC error box.

This message may be cited.

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TITLE:   GCN GRB OBSERVATION REPORT
NUMBER:  651
SUBJECT: GRB000424 Optical Observations
DATE:    00/04/27 09:50:23 GMT
FROM:    Mark Wagner at Ohio State U.  <rmw@as.arizona.edu>

R. M. Wagner, P. Eskridge (Ohio State U.), K. Vanlandingham,
J. Noel-Storr, N. Mirabal, & J. P. Halpern (Columbia U.)
report on behalf of the MDM Observatory GRB follow-up team:

"We imaged the error circle of the BeppoSAX WFC localization
of GRB 000424 (Piro, GCN #644) on two consecutive nights in
the R-band using the MDM 1.3m and 2.4m telescopes.  Between
April 26.15 and April 27.15, we see no variable object to a
5-sigma limiting magnitude of approximately R = 22.3.

This message may be cited."

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TITLE:   GCN GRB OBSERVATION REPORT
NUMBER:  660
SUBJECT: GRB000424, optical observations
DATE:    00/05/02 16:51:39 GMT
FROM:    Sarah Yost at Caltech  <yost@srl.caltech.edu>

S. Yost, A. Diercks, F. Harrison, R. Gal, V. Hradecky, D. Kaplan,
A. Mahabal, P. Mao (Caltech) report:

"We imaged the entire error circle of GRB000424 (Piro, GCN #644) with the 
CCD 13 instrument on the Palomar 60" telescope on two consecutive nights.
Exposures consisted of R-band 6x600s on April 27.17 UT and 7x600s on April
28.19 UT with seeing of approximately 1.5" and 1" respectively.
Subtraction of the two epochs reveals no variable candidates to the
detection limit of approximately R ~ 22.8 (field calibration by comparison
with USNO data)."
 
This message may be cited.

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TITLE:   GCN GRB OBSERVATION REPORT
NUMBER:  663
SUBJECT: GRB 000424 Optical Observations
DATE:    00/05/03 23:21:58 GMT
FROM:    Robert Uglesich at Columbia U./MDM Obs.  <rru@astro.columbia.edu>

R. Uglesich, N. Mirabal, J. P. Halpern, K. Vanlandingham,
J. Noel-Storr (Columbia U.), R. M. Wagner, P. Eskridge 
(Ohio State U.) report on behalf of the MDM Observatory 
GRB follow-up team:
 
"Further analysis of previously reported observations 
(GCN #651) of the BeppoSAX WFC localization of GRB 000424 
(Piro, GCN #644) using a sensitive image subtraction technique 
sets a 3-sigma limit of R > 22.8 on April 26.15 UT for any 
fading optical transient in the error circle. Magnitudes 
reported here are referenced to USNO-A2.0 catalog stars nearby."

This message may be cited.

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TITLE:   GCN GRB OBSERVATION REPORT
NUMBER:  664
SUBJECT: GRB000424, UBVRI field photometry
DATE:    00/05/03 23:31:21 GMT
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 preliminary UBVRcIc all-sky photometry for
an 11x11 arcmin field that covers the
error box for GRB000424 with the USNOFS 1.0-m telescope on one
marginally photometric night.  Stars brighter than
V=14 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/grb000424.dat
The current photometry has a potential external zero-point
error of about three percent.  The astrometry in this file
is based on linear plate solutions with respect to USNO-A2.0.
The internal errors are less than 100mas.
  Further calibration of this field will be performed if
an optical afterglow is identified.