[vsnet-grb-info 19498] GRB 170607A: Fermi GBM observation

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  21218
SUBJECT: GRB 170607A: Fermi GBM observation
DATE:    17/06/08 09:02:25 GMT
FROM:    Elisabetta Bissaldi at U.Innsbruk/IAPP  <Elisabetta.Bissaldi at uibk.ac.at>

R. Hamburg (UAH) and C. Meegan (UAH)
report on behalf of the Fermi GBM Team:


"At 23:17:59.57 UT on 07 June 2017, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 170607A (trigger 518570284 / 170607971),
which was also detected by the Swift/BAT (D'Ai et al. 2017, GCN 21214).
The GBM on-ground location is consistent with the Swift position.

The angle from the Fermi LAT boresight at the GBM trigger time is 100 degrees.

The GBM light curve consists of a sharp peak
with a duration (T90) of about 23 s (50-300 keV).
The time-averaged spectrum from T0-2.4 s to T0+14.0 s is
adequately fit by a power law function with an exponential
high-energy cutoff. The power law index is -1.40 +/- 0.04 and
the cutoff energy, parameterized as Epeak, is 154 +/- 13 keV.

The event fluence (10-1000 keV) in this time interval is
(9.6 +/- 0.3)E-06 erg/cm^2. The 1-sec peak photon flux measured
starting from T0+2.1 s in the 10-1000 keV band
is 15.5 +/- 0.6 ph/s/cm^2.


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