[vsnet-grb-info 19802] GRB 170906A: Fermi GBM detection

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  21839
SUBJECT: GRB 170906A: Fermi GBM detection
DATE:    17/09/06 21:32:38 GMT
FROM:    Rachel Hamburg at UAH  <rkh0007 at uah.edu>

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

"At 00:43:08.15 UT on 06 September 2017, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 170906A (trigger 526351393 / 170906030),
which was also detected by Swift (Siegel et al. 2017, GCN  21821).
The GBM on-ground location is consistent with the Swift position.

The angle from the Fermi LAT boresight at the GBM trigger time is 75
degrees.

The GBM light curve shows a multi-peaked structure
with a duration (T90) of about 79 s (50-300 keV).
The time-averaged spectrum from T0-2.6 s to T0+107.0 is
best fit by a Band function with Epeak = 288 +/- 12 keV,
alpha = -1.02 +/- 0.02, and beta = -2.09 +/- 0.04.

The event fluence (10-1000 keV) in this time interval is
(1.17 +/- 0.01)E-04 erg/cm^2. The 1-sec peak photon flux measured
starting from T0+33.4 s in the 10-1000 keV band
is 21.7 +/- 0.5 ph/s/cm^2.

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