Skip to main content
New Announcement Feature, Code of Conduct, Circular Revisions. See news and announcements

GCN Circular 20940

Subject
GRB 170325A: Fermi GBM observation
Date
2017-03-27T17:35:41Z (7 years ago)
From
Elisabetta Bissaldi at U.Innsbruk/IAPP <Elisabetta.Bissaldi@uibk.ac.at>
E. Bissaldi (Politecnico & INFN Bari), M. Stanbro,
and C. Meegan (UAH) report on behalf of the Fermi GBM Team:

"At 07:56:58.04 UT on 25 March 2017, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 170325A (trigger 512121423/170325331),
which was also detected by the Swift/BAT (Palmer et al. 2017, GCN 20938).
The GBM on-ground location is consistent with the Swift position.

The angle from the Fermi LAT boresight at the GBM trigger time is 60 degrees.

The GBM light curve consists of a single peak
with a duration (T90) of about 0.58 s (50-300 keV).
The time-averaged spectrum from T0-0.064 s to T0+0.192 s is
adequately fit by a power law function with an exponential
high-energy cutoff.  The power law index is -0.7 +/- 0.2 and
the cutoff energy, parameterized as Epeak, is 600 +/- 200 keV.

The event fluence (10-1000 keV) in this time interval is
(4.8 +/- 0.6)E-7 erg/cm^2. The 64-ms peak photon flux, measured
starting from T0 in the 10-1000 keV band, is 7.6 +/- 1.1 ph/s/cm^2.


The spectral analysis results presented above are preliminary;
final results will be published in the GBM GRB Catalog."
Looking for U.S. government information and services? Visit USA.gov