GCN Circular 19056
Subject
GRB 160221A: Fermi GBM observation
Date
2016-02-22T17:38:49Z (8 years ago)
From
C. Michelle Hui at MSFC/Fermi-GBM <c.m.hui@nasa.gov>
C. M. Hui (NASA/MSFC) and E. Bissaldi (Politecnico & INFN Bari)
report on behalf of the Fermi GBM Team:
"At 23:49:45.22 UT on 21 February 2016, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 160221A (trigger 477791389 / 160221993),
which was also detected by INTEGRAL (Mereghetti et al., GCN 19046).
The GBM on-ground location is consistent with the INTEGRAL position.
The angle from the Fermi LAT boresight at the GBM trigger time is 58 degrees.
The GBM light curve consists of a single pulse
with a duration (T90) of about 15 s (50-300 keV).
The time-averaged spectrum from T0-1.5 s to T0+5.6 s is
best fit by a power law function with an exponential
high-energy cutoff. The power law index is -1.15 +/- 0.16 and
the cutoff energy, parameterized as Epeak, is 67 +/- 7 keV.
The event fluence (10-1000 keV) in this time interval is
(1.55 +/- 0.14)E-06 erg/cm^2. The 1-sec peak photon flux measured
starting from T0+2.2 s in the 10-1000 keV band
is 4.0 +/- 0.3 ph/s/cm^2.
The spectral analysis results presented above are preliminary;
final results will be published in the GBM GRB Catalog."