[vsnet-grb-info 7209] GRB 090107: Swift detection of a burst

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  8782
SUBJECT: GRB 090107: Swift detection of a burst
DATE:    09/01/07 05:00:06 GMT
FROM:    David Palmer at LANL  <palmer at lanl.gov>

T. N. Ukwatta (GSFC/GWU), J. R. Cummings (NASA/UMBC),
N. Gehrels (NASA/GSFC), C. Guidorzi (U Ferrara),
S. T. Holland (CRESST/USRA/GSFC), J. A. Kennea (PSU),
W.B Landsman (GSFC), D. M. Palmer (LANL), M. Perri (ASDC) and
G. Stratta (ASDC) report on behalf of the Swift Team:

At 04:48:04 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 090107 (trigger=339295).  Swift could not slew
to this burst due to its proximity to the Sun. 
The BAT on-board calculated location is 
RA, Dec 302.426, +4.727 which is 
   RA(J2000) = 20h 09m 42s
   Dec(J2000) = +04d 43' 39"
with an uncertainty of 3 arcmin (radius, 90% containment, including 
systematic uncertainty).  The BAT light curve showed a double-peaked
structure with a duration of about 25 sec, with a possible additional
peak at T+75 sec.  The peak count rate was ~2000 counts/sec (15-350 keV),
at ~0 sec after the trigger. 

Due to the Sun observing constraint, Swift cannot slew to the 
BAT position.  There will thus be no XRT or UVOT data for this trigger. 

Burst Advocate for this burst is T. N. Ukwatta (tilan.ukwatta AT gmail.com). 
Please contact the BA by email if you require additional information
regarding Swift followup of this burst. In extremely urgent cases, after
trying the Burst Advocate, you can contact the Swift PI by phone (see
Swift TOO web site for information: http://www.swift.psu.edu/too.html.)