GCN Circular 9619
Subject
GRB 090706: Fermi GBM detection
Date
2009-07-06T15:06:24Z (15 years ago)
From
Arne Rau at MPE <arau@mpe.mpg.de>
Arne Rau (MPE) reports on behalf of the Fermi GBM Team:
"At 06:47:40.43 UT on 06 July 2009, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 090706 (trigger 268555662 / 090706283).
The on-ground calculated location, using the GBM trigger
data, is RA = 205.1, DEC = -47.1 (J2000 degrees,
equivalent to 13 h 40 m, -47 d 06 '), with an uncertainty
of 3.0 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 20 degrees.
The GBM light curve consists of two peaks
with a duration (T90) of about 100 s (8-1000 keV).
The time-averaged spectrum from T0-34.8s to T0+7.2 s is
adequately fit by a simple power law function with index -2.16 +/- 0.09
(chi squared 410 for 339 d.o.f.).
The event fluence (8-1000 keV) in this time interval is
(1.5 +/- 0.1)E-06 erg/cm^2. The 4-sec peak photon flux measured
starting from T0-30.7 s in the 8-1000 keV band
is 1.24 +/- 0.05 ph/s/cm^2.
The spectral analysis results presented above are preliminary;
final results will be published in the GBM GRB Catalog."