[vsnet-grb-info 26575] GRB 201017A: Fermi GBM detection

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  28675
SUBJECT: GRB 201017A: Fermi GBM detection
DATE:    20/10/18 00:40:30 GMT
FROM:    Suraj Poolakkil at UAH  <sp0076 at uah.edu>

S. Poolakkil (UAH), C. Meegan (UAH) and A. von Kienlin (MPE)
report on behalf of the Fermi GBM Team:

"At 09:46:32.63 UT on 17 October 2020, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 201017A(trigger 624620797 / 201017407),
which was also detected by the Swift/BAT (A. D'Ai et al. 2020, GCN 28666).
The GBM on-ground location is consistent with the Swift position.

The angle from the Fermi LAT boresight at the GBM trigger time is 98
degrees.

The GBM light curve consists of a single peak followed by some
extended emission with a duration (T90) of about 9 s (50-300 keV).
The time-averaged spectrum from T0-4.09 s to T0+5.12 s is
best fit by a power law function with an exponential
high-energy cutoff.  The power law index is -1.20 +/- 0.17 and
the cutoff energy, parameterized as Epeak, is 144 +/- 35 keV.

The event fluence (10-1000 keV) in this time interval is
(1.402 +/- 0.166)E-06 erg/cm^2. The 1-sec peak photon flux
measured starting from T0-0.89 s in the 10-1000 keV band
is 2.9 +/- 0.3 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/"