[vsnet-grb-info 8080] GRB 090706: Fermi GBM detection

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  9619
SUBJECT: GRB 090706: Fermi GBM detection
DATE:    09/07/06 15:06:24 GMT
FROM:    Arne Rau at MPE  <arau at 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."