[vsnet-grb-info 19380] GRB 170514A: Fermi GBM detection

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  21094
SUBJECT: GRB 170514A: Fermi GBM detection
DATE:    17/05/15 09:27:16 GMT
FROM:    Elisabetta Bissaldi at U.Innsbruk/IAPP  <Elisabetta.Bissaldi at uibk.ac.at>

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."