GCN Circular 8213
Subject
GRB 080905C: Fermi GBM detection
Date
2008-09-11T15:08:30Z (16 years ago)
From
Elisabetta Bissaldi at MPE <ebs@mpe.mpg.de>
E. Bissaldi, S. McBreen and A. von Kienlin (MPE)
report on behalf of the Fermi GBM Team:
"At 13:41:29 UT on 5 September 2008, the Fermi Gamma-ray Burst Monitor
triggered and located GRB 080905C (trigger 242314890 / 080905570).
The on-ground calculated location, using the Fermi GBM trigger
data, is RA = 96.9, Dec = -69.8 (J2000 degrees)
(equivalent to J2000 06h 28m, -69d 48'),
with a statistical uncertainty of 8 degrees (radius, 1-sigma
containment; there is additionally a systematic error which is
currently estimated to be 2 to 3 degrees). The angle from the
Fermi LAT boresight is 108 degrees.
This event comprises three pulses beginning at T0-4 s.
The main emission occurs during the first 11 sec and T90 (50-300 keV)
is about 28 s. The time-averaged spectrum from T0-3.6 s to T0+17 s
is adequately fit by a power law function with an exponential
high energy cutoff. The power law index is -0.90 +/-0.17 and
the cutoff energy, parameterized as Epeak, is 78.8 +/- 5.9 keV.
The fluence (25-1000 keV) is 4.6 (+/-0.3)E-06 erg/cm2
and the peak flux (25-1000 keV) on the 128 ms timescale
is 4.4 +/- 1.9 ph/cm2/s.
The spectral analysis results presented above are preliminary;
the final results will be published in the Fermi GBM GRB Catalog."