GCN Circular 8494
Subject
GRB 081107: Fermi GBM detection
Date
2008-11-07T15:51:17Z (16 years ago)
From
Andreas von Kienlin at MPE <azk@mpe.mpg.de>
A. von Kienlin (MPE) and E. Bissaldi (MPE)
report on behalf of the Fermi GBM Team:
"At 07:42:01.11 UT on 07 November 2008, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 081107 (trigger 247736522 / 081107321).
The on-ground calculated location, using the GBM trigger
data, is RA = 47.7, DEC = +17.0 (J2000 degrees,
equivalent to 03h 11m, 17d 00'), with an uncertainty
of 4.3 degrees (radius, 1-sigma containment,
statistical only; there is additionally a systematic
error which is currently estimated to be 2 to 3 degrees).
The angle from the Fermi LAT boresight is 52 degrees.
The GBM light curve shows one major structured peak
with a duration (T90) of about 2.2 s (8-1000 keV).
The time-averaged spectrum from T0-0.201 s to T0+1.655 s is
best fit by a Band function with Epeak = 65 +/- 3 keV,
alpha = 0.25 +/- 0.17, and beta = -2.80 +/- 0.15
(chi squared 542 for 481 d.o.f.).
The event fluence (8-1000 keV) in this time interval is
(1.64 +/- 0.28)E-06 erg/cm^2. The 1-sec photon flux measured
starting from T0-0.073 s in the 8-1000 keV band
is 11 +/- 3 ph/s/cm^2.
The spectral analysis results presented above are preliminary;
final results will be published in the GBM GRB Catalog."