[vsnet-grb-info 26324] GRB 200914A: Fermi GBM observation

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  28424
SUBJECT: GRB 200914A: Fermi GBM observation
DATE:    20/09/15 02:33:43 GMT
FROM:    Peter Veres at UAH  <veresp at gmail.com>

R. Dunwoody (UCD), J. Mangan (UCD) and C. Meegan (UAH) report on
behalf of the Fermi GBM Team:

"At 12:48:30.03 UT on 14 September 2020, the Fermi Gamma-Ray Burst
Monitor (GBM) triggered and located GRB 200914A (trigger 621780515 /
200914534) which was also detected by INTEGRAL (S. Mereghetti et al.,
GCN 28419). The GBM on-ground location is consistent with the INTEGRAL
position. The on-ground calculated location, using the GBM trigger
data, is provided in GCN 28417.

The angle from the Fermi LAT boresight at the GBM trigger time is 62 degrees.

The GBM light curve shows a long GRB with multiple features with a
duration (T90) of about 65 s (50-300 keV). The time-averaged spectrum
from T0 + 1.1 s to T0 + 24.6 s is best fit by a power law function
with an exponential high-energy cutoff.  The power law index is -0.89
+/- 0.03 and the cutoff energy, parameterized as Epeak, is 1260 +/-
140 keV.

The event fluence (10-1000 keV) in this time interval is (9.80 +/-
0.71)E-05 erg/cm^2. The 1-sec peak photon flux measured starting from
T0 + 1.95 s in the 10-1000 keV band is 7.9 +/- 0.2 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/"