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GCN Circular 15565

GRB 131202A: Fermi GBM Detection
2013-12-03T03:34:07Z (10 years ago)
Andrew Collazzi at NASA/MSFC/ORAU <>
Andrew C. Collazzi (NASA/ORAU) reports on behalf of the Fermi GBM

"At 15:12:10.85 UT on 2 December 2013, the Fermi Gamma-Ray Burst
Monitor triggered and located GRB 131202A (trigger 407689933 / 
131202633), which was also detected by the Swift/BAT and Swift/XRT
(Kocevski et al., GCN 15559). The GBM on-ground location is
consistent with the Swift/XRT position.

The angle from the Fermi LAT boresight is 86 degrees.

The GBM light curve consists of a single pulse with a duration (T90)
of 26 s (50-300 keV). We find the 1.024-s peak flux (10 - 1000 keV),
measured starting from T0-2.560, to be 1.5 +/- 0.2 ph/(s cm^2).
The time-averaged spectrum from T0-8.2 s to T0+11.3 s is best fit
by a power law function with an exponential high-energy cutoff.
The power law index is -1.10 +/- 0.25 and the cutoff energy,
parameterized as Epeak, is 288.4 +/- 172.0 keV.

The event fluence (10-1000 keV) in this time interval is
(1.6 +/- 0.4)E-06 erg/cm^2.

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