[vsnet-grb-info 7061] GRB 081206C: Fermi GBM detection

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  8644
SUBJECT: GRB 081206C: Fermi GBM detection
DATE:    08/12/09 21:03:11 GMT
FROM:    Sylvain Guiriec at UAH  <sylvain.guiriec at lpta.in2p3.fr>

S. Guiriec (UAH) and A.J. van der Horst (NASA/MSFC/ORAU)
report on behalf of the Fermi GBM Team:

"At 23:41:50.47 UT on 6 December 2008, the Fermi Gamma-Ray Burst Monitor
 triggered and located GRB 081206C (trigger 250299711 / 081206987).

The on-ground calculated location, using the GBM trigger data, is
 RA = 41.12, DEC = -14.42 (J2000 degrees, equivalent to +2h44m, -14d25'),
with an uncertainty of 7.7 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 71 degrees.

The GBM light curve shows a main pulse of ~20 seconds starting at ~T0-11s.
There is additional weak emission up to T0+83s.

The time-averaged spectrum from T0-9s to T0+11s is adequately fit by a
simple power-law function with index -1.35 +/- 0.04
(chi squared 505 for 481 d.o.f.).
The fluence (50-300 keV) in this time interval is
(1.19 +/- 0.04)E-6 erg/cm^2.
The 1-sec peak photon flux measured starting from T0-1s in the 50-300 keV
 band is 0.76 +/- 0.04 ph/s-cm^2.

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