[vsnet-grb-info 12921] GRB 130305A: Fermi GBM observation

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  14261
SUBJECT: GRB 130305A: Fermi GBM observation
DATE:    13/03/06 00:34:45 GMT
FROM:    Shaolin Xiong at UAH  <sx0002 at uah.edu>

Hoi-Fung Yu (MPE) and Shaolin Xiong (UAH)
report on behalf of the Fermi GBM Team:

"At 11:39:11.37 UT on 05 March 2013, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 130305A (trigger 384176354 / 130305486),
which was also detected by the Fermi/LAT (S. Guiriec et al., GCN 14260) and
the Swift/BAT (Cummings et al., GCN 14257).
The GBM on-ground location is consistent with the Swift position.
The angle from the Fermi LAT boresight is about 44 degrees.

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

The GBM light curve shows single pulse with a tail
with a duration (T90) of about 29 s (50-300 keV).
The time-averaged spectrum from T0-0 s to T0+30 s is best fit by
a Band function with Epeak = 640 +/- 23 keV,
alpha = -0.67 +/- 0.02, and beta = -2.4 +/- 0.1.

The event fluence (10-1000 keV) in this time interval is
(5.7 +/- 0.07)E-5 erg/cm^2. The 1-sec peak photon flux measured
starting from T0+5.2 s in the 10-1000 keV band
is 25.4 +/- 0.3 ph/s/cm^2.

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