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GCN Circular 22585

GRB 180402A: Fermi GBM detection
2018-04-02T21:52:22Z (6 years ago)
Christian Malacaria at U of Alabama/MSFC <>
C. Malacaria (NASA-MSFC/USRA) reports on behalf of the Fermi GBM Team:

"At 09:44:59.37 UT on 02 April 2018, the Fermi Gamma-Ray Burst
Monitor triggered and located GRB 180402A
(trigger 544355104 / 180402406).

The event was also detected by the Swift/BAT
(Lien et al. 2018, GCN 22580).
The GBM on-ground location is consistent with the Swift position.

The LAT boresight angle is 90 degrees.

The duration (T90) is 0.448 +/- 0.326 s (8-1000 keV).
The time-averaged spectrum from T0-0.1 s to T0+0.2 s is best fit
by a Band function.
The best-fit parameters are: Alpha = 2.23 +/- 2.03,
Beta = -1.35 +/- 0.04, Epeak = 123.80 +/- 44.00 keV.

The event fluence (8-1000 keV) in this time interval is
(8.69 +/- 0.62)E-07 erg/cm^2.
The 1-sec peak photon flux measured starting from T0+0 s in the
10-1000 keV band is 17.5 +/- 1.4 ph/s/cm^2.

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