[vsnet-grb-info 20012] GRB 171103A: Fermi GBM observation

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  22100
SUBJECT: GRB 171103A: Fermi GBM observation
DATE:    17/11/05 16:12:21 GMT
FROM:    Peter Veres at UAH  <veresp at gmail.com>

P Veres (UAH) reports on behalf of the Fermi GBM Team:

"
GRB 171103A, detected by Swift (Ukwatta et al, GCN #22095) is clearly
visible in the GBM data. It was not possible for GBM to trigger at
this time because GBM was still in trigger mode for a transient that
occurred 190 s earlier (171103963 / 531443246).

The angle from the Fermi LAT boresight at the Swift trigger time is
102 degrees.

The GBM light curve shows a single pulse with a duration (T90) of
about 1.1 s (50-300 keV). The time-averaged spectrum for a 0.4 s
interval starting from 23:10:31.951 UT is best fit by a power law
function with an exponential high-energy cutoff.  The power law index
is -0.74 +/- 0.05 and the cutoff energy, parameterized as Epeak, is
2.1 +/- 0.2 MeV.

The event fluence (10-1000 keV) in this time interval is
(2.7 +/- 0.1)E-6 erg/cm^2. The 64-ms peak photon flux measured
starting from 23:10:32.082 in the 10-1000 keV band is
30.3 +/- 2.0 ph/s/cm^2.

"