[vsnet-grb-info 6608] GRB 080906B: Fermi GBM detection

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  8214
SUBJECT: GRB 080906B: Fermi GBM detection
DATE:    08/09/11 16:01:22 GMT
FROM:    Elisabetta Bissaldi at MPE  <ebs at mpe.mpg.de>

E. Bissaldi, S. McBreen and A. von Kienlin (MPE) 
report on behalf of the Fermi GBM Team: 




"At 05:05:11 UT on 6 September 2008, the Fermi Gamma-ray Burst Monitor
triggered and located GRB 080906B (trigger 242370312 / 080906212).
The on-ground calculated location, using the Fermi GBM 
trigger data, is RA = 185.5, Dec = -8.6 (J2000 degrees) 
(equivalent to J2000 12h 22m, -08d 36'), 
with a statistical uncertainty of 3.3 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 32 degrees. 

This GRB consists of one main emission phase comprising
several overlapping pulses, with an estimated T90 (50-300 keV) 
of about 5 s. The time-averaged spectrum from T0 to T0+3.8 s is 
best fit by a Band function with the following parameters:
alpha = -0.07 +/- 0.09             
beta = -2.10 +/- 0.07             
Epeak = 125.3 +/- 6.6 keV         

The fluence (25-1000 keV) is 10.9 (+/-0.1)E-06 erg/cm2.
The peak flux (25-1000 keV) on the 128 ms timescale
is 22 +/- 4 ph/s/cm2.



The spectral analysis results presented above are preliminary;
the final results will be published in the Fermi GBM GRB Catalog."