GRB 050908: Swift detection of a burst

TITLE: GCN GRB OBSERVATION REPORT
NUMBER: 3942
SUBJECT: GRB 050908: Swift detection of a burst
DATE: 05/09/08 06:28:38 GMT
FROM: Hans Krimm at NASA-GSFC krimm@milkyway.gsfc.nasa.gov

M. Goad (U. Leicester), H. Krimm (GSFC/USRA), D. Burrows (PSU), M. Chester (PSU), N. Gehrels (GSFC), C. Markwardt (GSFC/UMD), J. Osborne (U. Leicester), C. Pagani (PSU), K. Page (U. Leicester), D. Palmer (LANL), A. Parsons (GSFC) on behalf of the Swift team:

At 05:42:31 UT, Swift-BAT triggered and located GRB050908 (trigger=154112). The BAT on-board calculated location is RA,Dec 20.464, -12.971 {01h 21m 51s, -12d 58′ 16″} (J2000), with an uncertainty of 3 arcmin (radius, 90% containment, stat+sys). The BAT light curve shows a roughly triangular shape with a possible two peaks and total duration of ~25 seconds. The peak count rate is ~1000 cts/sec.

The S/C slewed immediately and the XRT began observations at 05:44:18 UT, T+106.2 seconds. The instrument was not able to calculate an on-board centroid. No bright source was initially apparent, but the initial lightcurve suggests that a source in the field of view may have brightened and then decayed in the first few minutes of the observation. Further analysis will require processing of the full telemetry data following the next ground station contact.

The UVOT began observations at 05:44:15.6. Further analysis will require processing of the full telemetry data following the next ground station contact.