Skip to main content
Testing. You are viewing the public testing version of GCN. For the production version, go to
New Announcement Feature, Code of Conduct, Circular Revisions. See news and announcements

GCN Circular 3748

GRB050803: Swift-BAT detection of a very long burst
2005-08-03T20:10:23Z (19 years ago)
Scott Barthelmy at NASA/GSFC <>
D.L. Band (GSFC-UMBC), S. Barthelmy (GSFC), P. Boyd (GSFC-UMBC), P. Brown (PSU),   
D. Burrows (PSU), M. Chester (PSU), J. Cummings (GSFC/NRC), N. Gehrels (GSFC),     
C. Markwardt (GSFC), J. Nousek (PSU), K. Page (U. Leicester), C. Pagani (PSU),     
D. Palmer (LANL), T. Sakamoto (GSFC), J. Racusin (PSU)                             
on behalf of the Swift team:                                                       
At 19:14:00 UT, Swift-BAT triggered and located GRB050803 (trigger=148833).        
The spacecraft slewed immediately.  The BAT on-board calculated location           
is RA,Dec 350.650d,+5.800d {23h 22m 36s,+05d 48' 00"} (J2000), with an             
uncertainty of 3 arcmin (radius, 90% containment, stat+sys).  The BAT light        
curve shows a multi-peak structure with a total duration of at least 150 sec.      
There is a fairly strong short peak at T+145 sec.  The peak count rate was         
~1000 counts/sec (15-350 keV), at ~80 seconds after the trigger.                   
The XRT began observing at 19:16:31.6 UT, 151.6 seconds after the BAT trigger.     
An uncatalogued, rapidly fading X-ray source was detected at an RA and Dec of      
23h 22m 37.7s, 05d 47m 7.4s (J2000; 90% containment uncertainty of 6 arcsec),      
which is 58.4" from the BAT position.                                              
The UVOT began settled exposures about 3 minutes after the burst.  Using a         
preliminary ground-processed 100-sec image, the upper limit is 18.5 (3 sigma)      
in the V band.
We are currently in the portion of the orbits where the spacecraft does not        
pass over the Malindi downlink station.  Therefore, it will be ~4 hours            
before we have access to the full data set for the refined analyses.
Looking for U.S. government information and services? Visit