GCN Circular 25636

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

"At 17:19:36.26 UT on 3 September 2019, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 190903A (trigger 589223981/190903722).

The on-ground calculated location, using the GBM trigger
data, is RA = 62.43 , DEC = -64.86  (J2000 degrees,
equivalent to 11h 32m, -17d 46'), with an uncertainty
of 6.3 degrees (radius, 1-sigma containment).

The angle from the Fermi LAT boresight is 86  degrees.

The GBM light curve consists of a single short spike
with a duration (T90) of about 0.27s (50-300 keV).
The time-averaged spectrum from T0-0.064s to T0+0.128s is
adequately fit by a Band function with Epeak = 824 +/- 308 keV,
alpha = -0.79 +/- 0.13, and beta = -2.15 +/- 0.36

The event fluence (10-1000 keV) in this time interval is
 (7.8 +/- 0.65)E-07 erg/cm^2. The 1-sec peak photon flux measured
starting from T0-0.38s in the 10-1000 keV band is 3.01 +/- 0.23 ph/s/cm^2."

The spectral analysis results presented above are preliminary;
final results will be published in the GBM GRB Catalog:
https://heasarc.gsfc.nasa.gov/W3Browse/fermi/fermigbrst.html
For Fermi GBM data and info,
please visit the official Fermi GBM Support Page:
https://fermi.gsfc.nasa.gov/ssc/data/access/gbm/