Skip to main content
Testing. You are viewing the public testing version of GCN. For the production version, go to
New Announcement Feature, Code of Conduct, Circular Revisions. See news and announcements

GCN Circular 21094

GRB 170514A: Fermi GBM detection
2017-05-15T09:27:16Z (7 years ago)
Elisabetta Bissaldi at U.Innsbruk/IAPP <>
E. Bissaldi (Politecnico & INFN Bari) and C. Meegan (UAH)
report on behalf of the Fermi GBM Team:

"At 04:18:38.88 UT on 14 May 2017, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 170514A (trigger 516428323 / 170514180).
The on-ground calculated location, using the GBM trigger
data, is

RA, Dec = 122.10, -25.30

(J2000 degrees, equivalent to 08h 08m, -25d 18'),
with an uncertainty of 2.2 degrees (radius, 1-sigma containment,
statistical only; there is additionally a systematic
error which we have characterized as a core-plus-tail model, with 90% of
GRBs having a 3.7 deg error and a small tail suffering a larger than 10 deg
systematic error [Connaughton et al. 2015, ApJS, 216, 32]).

The angle from the Fermi LAT boresight at the GBM trigger time is 58 degrees.

The GBM light curve shows two distinct emission episodes
with a duration (T90) of about 104 s (50-300 keV).
The time-averaged spectrum from T0 s to T0+30 s
and from T0+75 s to T0+100 s is adequately fit by
a power law function with an exponential
high-energy cutoff. The power law index is -1.53 +/- 0.02 and
the cutoff energy, parameterized as Epeak, is 150 +/- 7 keV.

The event fluence (10-1000 keV) in this time interval is
(2.26 +/- 0.04)E-05 erg/cm^2. The 1-sec peak photon flux measured
starting from T0+83.4 s in the 10-1000 keV band
is 13.0 +/- 0.3 ph/s/cm^2.

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