[vsnet-grb-info 15158] GRB 140623A / iPTF14cyb: Fermi GBM detection

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  16450
SUBJECT: GRB 140623A / iPTF14cyb: Fermi GBM detection
DATE:    14/06/24 14:58:54 GMT
FROM:    Andreas von Kienlin at MPE  <azk at mpe.mpg.de>

A. von Kienlin (MPE) reports on behalf of the Fermi GBM Team:

"At 05:22:06.60 UT on 23 June 2014, the Fermi Gamma-Ray Burst Monitor
triggered 
and located GRB 140623A (trigger 425193729 / 140623224), which was observed 
by the intermediate Palomar Transient Factory beginning 11 minutes after 
trigger time, and was reported in GCN 16425 (Bhalerao et al. 2014) as
iPTF14cvb.

The on-ground calculated location, using the GBM trigger
data, is RA = 202.8, DEC = 75.8 (J2000 degrees,
equivalent to 13h 31m, 75d 48'), with an uncertainty
of 5.6 degrees (radius, 1-sigma containment,
statistical only; there is additionally a systematic
error which is currently estimated to be 2 to 3 degrees).
The angle from the Fermi LAT boresight is 32 degrees.

The GBM light curve shows a multiple-peak structure  
with a duration (T90) of about 110 s (50-300 keV).
The time-averaged spectrum from T0-49.2 s to T0+73.7 s is
well fit by a power law function with an exponential
high-energy cutoff.  The power law index is -1.46 +/- 0.1  and
the cutoff energy, parameterized as Epeak, is 350(+220/-100) keV

The event fluence (10-1000 keV) in this time interval is
(6.8 +/- 0.6)E-06 erg/cm^2. The 1.024-sec peak photon flux measured
starting from T0-3.65 s in the 10-1000 keV band
is 1.9 +/- 0.2 ph/s/cm^2.

The spectral analysis results presented above are preliminary;
final results will be published in the GBM GRB Catalog."