[vsnet-grb-info 2027] GRB050824: Swift-BAT detection of a burst

[GCN Circulars]

TITLE:   GCN GRB OBSERVATION REPORT
NUMBER:  3866
SUBJECT: GRB050824: Swift-BAT detection of a burst
DATE:    05/08/25 00:31:30 GMT
FROM:    Scott Barthelmy at NASA/GSFC  <Scott at lheamail.gsfc.nasa.gov>

S. Campana (INAF-OAB), S. Barthelmy (GSFC), D. Burrows (PSU),
J. Cummings (GSFC/NRC), N. Gehrels (GSFC), S. Hunsberger (PSU),
M. Ivanushkina (PSU), F. Marshall (GSFC), D. Palmer (LANL),
G. Tagliaferri (INAF-OAB),
on behalf of the Swift team:

At 23:12:16 UT, Swift-BAT triggered and located GRB050824 (trigger=151905).
This was a 64-sec image trigger.  The spacecraft did not automatically slew
due to proximity to the moon (25 degrees).  Hence there will be no immediate
results from XRT or UVOT.  However, a TOO is being planned for this target.
The BAT on-board calculated location is RA,Dec 12.237d,+22.592d
{00h 48m 57s,+22d 35' 31"} (J2000), with an uncertainty of 3 arcmin
(radius, 90% containment, stat+sys).  The BAT light curve shows a broad peak
from T+30 to T+70 sec.  The emission is present only in the 15-50 keV band.
The peak count rate was ~500 counts/sec (15-50 keV) at ~40 seconds
after the trigger.  At this early stage of the analysis we think this is
likely a GRB, as there is no known gamma-ray source at this location
in the SIMBAD database and the galactic latitude is -40 degrees.