Skip to main content
New Announcement Feature, Code of Conduct, Circular Revisions. See news and announcements

GCN Circular 3490

Subject
GRB 050525B: Swift-BAT observations
Date
2005-05-26T18:09:33Z (19 years ago)
From
Jay R. Cummings at NASA/GSFC/Swift <jayc@milkyway.gsfc.nasa.gov>
J. Cummings (GSFC/NRC), L. Barbier (GSFC), S. Barthelmy (GSFC),
E. Fenimore (LANL), N. Gehrels (GSFC), D. Hullinger (UMD),
H. Krimm (GSFC/USRA), C. Markwardt (GSFC/UMD), T. Mitani (ISAS),
D. Palmer (LANL), A. Parsons (GSFC), T. Sakamoto (GSFC/NRC),
G. Sato (ISAS), M. Suzuki (Saitama), J. Tueller (GSFC),

on behalf of the Swift-BAT team:

From 00:49:50 to approximately 00:50:06 UT Swift-BAT recorded
high rates from GRB 050525B (Mereghetti et al., GCN Circ 3477, 
Golenetskii et al. GCN Circ 3474).  The burst was not in the BAT 
field of view, and was primarily detected in the high energy 
band (>100 keV) through the side or bottom of the instrument.  
Thus BAT did not find a position, and detailed information 
about the flux and spectrum is not available.

The light curve is complex.  Peaks occur at 00:49:50, 00:49:52,
00:49:55, and a complex of peaks with the most intense flux from
00:49:59 to 00:50:06.  The peak rate in a 64 ms interval was
recorded at 00:50:00.12.

(The association of the small peak at 00:49:39, which initiated 
BAT trigger 130094, with the others is uncertain, because GRB
050525B was not coded by the mask and, unlike the other peaks, 
the trigger peak's energy profile is not obviously that of 
exposure through the side or bottom of the instrument.)

The light curve is available at:
http://swift.gsfc.nasa.gov/docs/swift/results/releases/images/GRB050525b/

We note that GRB 050525A was well below the Earth horizon from 
the point of view of Swift at the time of this burst, and 
therefore cannot be connected with this GRB 050525B event.
Looking for U.S. government information and services? Visit USA.gov