TITLE:   GCN CIRCULAR
NUMBER:  15053
SUBJECT: GRB 130727A: Fermi GBM detection
DATE:    13/07/28 01:49:33 GMT
FROM:    Adam Goldstein at Fermi-GBM/UAH  <adam.m.goldstein@msfc.nasa.gov>

A. Goldstein (ORAU/NASA MSFC) reports on behalf of the Fermi GBM Team:

At 16:45:20.91 UT on 27 July 2013, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 130727A (trigger 396636323 /130727698)
which was also detected by the Swift BAT (Stroh et al. 2013, GCN 15046).
The GBM on-ground location is consistent with the Swift position;
the angle from the Fermi LAT boresight is 134 degrees.

The GBM light curve consists of one main pulse with substructure
with a duration (T90) of about 13.0 s (50-300 keV).  The 
time-averaged spectrum from T0=-1.0 s to T0+12.0 s is adequately fit 
by a Band function with Epeak = 118 +/- 17 keV, alpha = -1.1 +/- 0.1, 
and beta = -2.2 +/- 0.1.

The event fluence (10-1000 keV) in this time interval is 
(8.9 +/- 0.3)E-06 erg/cm^2. The 1-sec peak photon flux measured starting 
from T0+6.1 s in the 8-1000 keV band is 11.1 +/- 0.6 ph/s/cm^2.

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