[vsnet-grb-info 13193] GRB 130502B: Fermi GBM detection of a burst

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  14530
SUBJECT: GRB 130502B: Fermi GBM detection of a burst
DATE:    13/05/02 20:15:24 GMT
FROM:    George A. Younes at USRA/NASA/MSFC  <younes.ge at gmail.com>

A. Von Kienlin (MPE) and G. Younes (NASA/USRA) report on behalf of the Fermi GBM Team:

"At 07:51:11.76 UT on April 2 2013, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 130502B (trigger 389173874 / 130502327).

The on-ground calculated location, using the GBM trigger
data, is RA = 74.5, DEC = 70.6 (J2000 degrees), with an uncertainty
of 1.0 degree (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 47 degrees.

This burst was also independently detected by INTEGRAL SPI-ACS.

The GBM light curve consists of multiple spikes
with a duration (T90) of about 24 s (50-300 keV).
The time-averaged spectrum from T0-4.1 s to T0+71.7 s is
best fit by a Band function with Epeak = 323.00 +/- 7.00 keV,
alpha = -0.75 +/- 0.01, and beta = -2.47 +/- 0.07.

The event fluence (10-1000 keV) in this time interval is
(1.21 +/- 0.01)E-04 erg/cm^2. The 1.024 sec peak photon flux
measured starting from T0+30.3 s in the 8-1000 keV band
is 45.8 +/- 0.5 ph/s/cm^2.

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