TITLE:   GCN CIRCULAR
NUMBER:  21297
SUBJECT: GRB 170705A: Fermi GBM observation
DATE:    17/07/05 18:03:09 GMT
FROM:    Elisabetta Bissaldi at U.Innsbruk/IAPP  <Elisabetta.Bissaldi@uibk.ac.at>

E. Bissaldi (Politecnico & INFN Bari) and C. Meegan (UAH)
report on behalf of the Fermi GBM Team:

"At 02:45:51.03 UT on 5 July 2017, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 170705A (trigger 520915556 / 170705115),
which was also detected by the Swift/BAT (Starling et al. 2017, GCN 21289).
The GBM on-ground location is consistent with the Swift position.

The angle from the Fermi LAT boresight at the GBM trigger time is 118 
degrees.

The GBM light curve shows two peaks
with a duration (T90) of about 22 s (50-300 keV).
The time-averaged spectrum from T0-2 s to T0+20 s is
adequately fit by a Band function with Epeak = 100 +/- 10  keV,
alpha = -0.88 +/- 0.07, and beta = -2.38 +/- 0.09.

The event fluence (10-1000 keV) in this time interval is
(1.37 +/- 0.04)E-05 erg/cm^2. The 1-sec peak photon flux measured
starting from T0+9.4 s in the 10-1000 keV band
is 22.5 +/- 0.5 ph/s/cm^2.


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