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GCN Circular 25180

GRB 190727B: Fermi GBM observations
2019-07-28T04:43:17Z (5 years ago)
Peter Veres at UAH <>
P. Veres and C. Meegan (both UAH) report on behalf of the Fermi GBM Team:

At 20:17:56.45 UT on 27 July 2019, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 190727B (trigger 585951481/190727846), which was
also detected by the Swift/BAT (Lien et al., GCN 25176). The GBM on-ground
location is consistent with the Swift position.

The angle from the Fermi LAT boresight is 46 degrees.

The GBM light curve consists of multiple overlapping pulses with a duration
(T90) of about 35 s (50-300 keV). The time-averaged spectrum from T0 to
T0+44 s is adequately fit by a power law function with an exponential
high-energy cutoff. The power law index is -1.26 +/- 0.01 and the cutoff
energy, parameterized as Epeak, is 621 +/- 26 keV.

The event fluence (10-1000 keV) in this time interval is (7.02 +/-
0.05)E-05 erg/cm^2. The 1-second peak photon flux measured starting from
T0+21.8 s in the 10-1000 keV band is 43.0 +/- 0.4 ph/s/cm^2.

The spectral analysis results presented above are preliminary; final
results will be published in the GBM GRB Catalog: For Fermi GBM
data and information, please visit the official Fermi GBM Support Page:
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