[vsnet-grb-info 8847] GRB 100117A: Fermi GBM detection

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  10345
SUBJECT: GRB 100117A: Fermi GBM detection
DATE:    10/01/18 19:14:16 GMT
FROM:    Bill Paciesas at UAH  <bill.paciesas at nasa.gov>

W. Paciesas (UAH) reports on behalf of the Fermi GBM Team:

"At 21:06:19.66 UT on 17 January 2010, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 100117A (trigger 285455181 / 100117879)
which was also detected by the Swift-BAT (De Pasquale et al. 2010, GCN
10336).
The GBM on-ground location is consistent with the Swift position.
The angle from the Fermi LAT boresight is 86 degrees.

The GBM light curve consists of one pulse
with a duration (T90) of about 0.4 s.
The time-averaged spectrum from T0-0.128 s to T0+0.256 s is
adequately fit by a power law function with an exponential
high energy cutoff. The power law index is -0.14 (+0.33 / -0.27) and
the cutoff energy, parameterized as Epeak, is 287 (+74 / -50) keV
(CSTAT 548 for 484 d.o.f.).

The event fluence (8-1000 keV) in this time interval is
(4.1 +/- 0.5 )E-07 erg/cm^2. The 0.256-sec peak photon flux measured
starting from T0-0.128 s in the 8-1000 keV band
is 6.1 +/- 0.4 ph/s/cm^2.

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