[vsnet-grb-info 16502] GRB 150426A: Fermi GBM detection

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  17783
SUBJECT: GRB 150426A: Fermi GBM detection
DATE:    15/04/28 18:33:49 GMT
FROM:    Binbin Zhang at UAH  <binbin.zhang at uah.edu>

Bin-Bin Zhang (UAH) report on behalf of the Fermi GBM team:

"At 14:15:31.22 on April 26 2015, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 150426A (trigger 451750534/150426594).
The GBM on-ground location, using the Fermi GBM trigger
data, is RA = 17.6, Dec = -30.2 with an uncertainty of 1.5
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 of the
burst direction to the Fermi LAT boresight is 136 degrees.


The GBM light curve consists of multiple peaks with a duration (T90)
of about 23 s (50-300 keV). The time-averaged spectrum from T0+0s to
T0+23 s is well fit by a BAND function with Epeak = 109.9 +/- 10.6 keV,
alpha = -1.0 +/- 0.1 and Beta = -2.3 +/- 0.1. The event fluence (10-1000 keV)
in this time interval is (1.15 +/- 0.04)E-05 erg/cm^2. The 1.0-sec
peak photon flux measured starting from T0+13.8 s in the 10-1000 keV
band is 22.1 +/- 0.7 ph/s/cm^2.


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