GRB 170514A

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."

S. Matsukawa, A. Yoshida, T. Sakamoto, Y. Kawakubo, M. Moriyama,
Y. Yamada, A. Tezuka (AGU), K. Yamaoka (Nagoya U), S. Nakahira (RIKEN),
I. Takahashi (IPMU), Y. Asaoka, S. Ozawa, S. Torii (Waseda U), Y. Shimizu,
T. Tamura (Kanagawa U), W. Ishizaki (ICRR), M. L. Cherry (LSU),
S. Ricciarini (U of Florence), A. V. Penacchioni, P. S. Marrocchesi (U of Siena)
and the CALET collaboration:

The long-duration GRB 170514A (Bissaldi et al., GCN Circ. 21094
Loading...
 
 ;
Konus-Wind trigger time on 04:18:42.056 UT) triggered the CALET
Gamma-ray Burst Monitor (CGBM) at 04:19:59.08 on 14 May 2017.
The burst signal was seen by all CGBM instruments.  Because of a
problem in one of the ground alert processing script, the GCN notice
was not distributed automatically for this event.  Note that the CGBM
triggered at the 2nd bright burst episode which was ~1 min after the
initial peak.

The light curve of the SGM shows two separated peaks.  The initial peak,
which triggered Fermi-GBM and Konus-Wind, shows the emission around T-70 sec.
The 2nd peak starts from T-1 sec, peaks at T+0 sec and ends at T+10 sec.
The T90 duration measured by the SGM data is 7.8 +- 0.6 sec (40-1000 keV).

The light curve is available at

http://cgbm.calet.jp/cgbm_trigger/flight/1178770293/

The CALET data used in this analysis are provided by the Waseda
CALET Operation Center located at the Waseda University.