[vsnet-grb-info 14163] GRB 131108A: Fermi GBM observation

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  15477
SUBJECT: GRB 131108A: Fermi GBM observation
DATE:    13/11/09 17:50:57 GMT
FROM:    George A. Younes at USRA/NASA/MSFC  <younes.ge at gmail.com>

G. Younes (USRA/NASA-MSFC) reports on behalf of the Fermi GBM Team:

At 20:41:55.76 UT on 08 November 2013, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 131108A (trigger 405636118/131108862), which also
triggered onboard the Fermi/LAT (Racusin et al, GCN 15464). The GBM on-ground
location is consistent with the Swift/XRT location of the candidate afterglow
(M. C. Stroh and J. A. Kennea, GCN 15468).

The burst was bright enough that it also resulted in an Autonomous Repoint Request (ARR).

The GBM light curve consists of a multiple-peak structure with a duration
(T90) of about 19 s (50-300 keV). The time-averaged spectrum from
T0 to T0+21 s is adequately fit by a Band function with Epeak =
373 +/- 14 keV, alpha = -0.91 +/- 0.02, and beta = -2.6 +/- 0.1.

The event fluence (10-1000 keV) in this time interval is
(3.65 +/- 0.04)E-05  erg/cm^2. The 1-sec peak photon flux measured
starting from T0+0.1 s in the 10-1000 keV band is 19.8 +/- 0.4 ph/s/cm^2.

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