[vsnet-grb-info 17018] GRB 150912A: Fermi GBM observation

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  18299
SUBJECT: GRB 150912A: Fermi GBM observation
DATE:    15/09/12 21:34:34 GMT
FROM:    Elisabetta Bissaldi at U.Innsbruk/IAPP  <Elisabetta.Bissaldi at uibk.ac.at>

E. Bissaldi (INFN Bari) reports on behalf of the Fermi GBM Team:


"At 10:37:38.70 UT on 12 September 2015, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 150912A (trigger 463747062/150912443),
which was also detected by INTEGRAL (Mereghetti et al. 2015, GCN 18291).
The GBM on-ground location is consistent with the INTEGRAL position.

The angle from the Fermi-LAT boresight at the GBM trigger time is 67 degrees.

The GBM light curve consists of a single peak
with a duration (T90) of about 30 s (50-300 keV).
The time-averaged spectrum from T0-6 s to T0+22 s is
best fit by a power law function with an exponential
high-energy cutoff. The power law index is -1.11 +/- 0.10 and
the cutoff energy, parameterized as Epeak, is 250 +/- 40 keV.

The event fluence (10-1000 keV) in this time interval is
(4.5 +/- 0.3)E-06 erg/cm^2. The 1-sec peak photon flux, measured
starting from T0+2.2 s in the 10-1000 keV band,
is 2.82 +/- 0.25 ph/s/cm^2.


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