[vsnet-grb-info 15509] GRB 140907A: Fermi GBM Detection

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  16798
SUBJECT: GRB 140907A: Fermi GBM Detection
DATE:    14/09/08 15:32:05 GMT
FROM:    Binbin Zhang at UAH  <binbin.zhang at uah.edu>

Bin-Bin Zhang (UAH) reports on behalf of the Fermi GBM Team:

"At 16:07:11.80 UT on 07 September 2014, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 140907A (trigger 431798834 / 140907672), which
was also detected by the Swift/BAT (Krimm et al 2014, GCN 16788)
The GBM on-ground location is consistent with the Swift position.

The angle from the Fermi LAT boresight is 16 degrees.

The GBM light curve consists of a single pulse with multiple peaks.
The total duration (T90) is about 35 +/- 10 s (50-300 keV).
The time-averaged spectrum from T0-12 s to T0+22 s is
best fit by a power law function with an exponential
high-energy cutoff. Â The power law index is -0.97 +/- 0.08 Â and
the cutoff energy, parameterized as Epeak, is 113 +/- 7 keV.

The event fluence (10-1000 keV) in this time interval is
(5.5 +/- 0.2)E-06 erg/cm^2. The 1.024-sec peak photon flux measured
starting from T0+8.9 s in the 10-1000 keV band
is 4.2 +/- 0.3 Â ph/s/cm^2.

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