GCN Circular 3237
Subject
Swift-BAT Detection of GRB 050412: A Bright, Long Burst
Date
2005-04-12T07:21:04Z (20 years ago)
From
Jay R. Cummings at NASA/GSFC/Swift <jayc@milkyway.gsfc.nasa.gov>
J. Cummings (GSFC/NRC), L. Barbier, S. Barthelmy (GSFC),
E. Fenimore (LANL), M. Galassi (LANL), N. Gehrels (GSFC),
D. Hullinger (UMD), H. Krimm (GSFC/USRA),
C. Markwardt (GSFC/UMD), D. Palmer (LANL), A. Parsons (GSFC),
T. Sakamoto (GSFC/NRC), G. Sato (ISAS), M. Suzuki (Saitama),
M. Tripicco (GSFC-SSAI), J. Tueller (GSFC), D. Burrows (PSU),
J. Kennea (PSU), V. Mangano (IASF-CNR)
on behalf of the Swift team:
At 05:44:03 UT, Swift-BAT triggered on burst GRB 050412
(trigger=114485) and began to slew 35 seconds after the trigger.
The BAT onboard position is RA, Dec = 181.120, -1.252 (J2000)
with an estimated error of <4 arcminutes. The lightcurve shows
a complex multi-peaked emission from 9 seconds before the
trigger to at least 15 seconds after. There was strong flux in
all energy bands from 15 to 350 keV. The 1 second peak count
rate is 0.8 ph/cm2/s (15-350 keV).
We note that this burst is well suited for ground-based
followup, being anti-Sunward, far from the Moon, away from
the Galactic plane, and equatorial.
No object was detected by the XRT on-board software, beginning
at about T+100 seconds. However, the XRT counting rate is
slightly elevated, indicating a possible weak counterpart.
Further information from all 3 Swift instruments will be
available when data from the Malindi ground station are
received and processed at about 11:00 UT.