[vsnet-grb-info 9966] GRB 101123A: Fermi GBM detection

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  11423
SUBJECT: GRB 101123A: Fermi GBM detection
DATE:    10/11/25 01:16:48 GMT
FROM:    Sylvain Guiriec at UAH  <sylvain.guiriec at lpta.in2p3.fr>

Sylvain Guiriec (UAH)
reports on behalf of the Fermi GBM Team:

At 22:51:34.97  UT on 23 November 2010, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 101123A (trigger 312245496 / 101123952).

The on-ground calculated location, using the GBM trigger
data, is RA = 131.24, DEC = 6.51 (J2000 degrees,
equivalent to 08 h 54 m 27 s,  06 d 30 ' 36 ''), with an uncertainty
of 1 degree (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 86 degrees.

GBM triggered on a weak pulse followed by three separate emission periods
with a total duration (T90) of about 105 s (50-300 keV).
The time-averaged spectrum of the brightest part of the burst from T0+42 s
 to T+57 s is adequately fit by a Band function with Epeak = 476 +/- 11 keV,
alpha = -0.75 +/- 0.01, and beta = -2.14 +/- 0.03.

The event fluence (10-1000 keV) over the T90 duration is
(1.283 +/- 0.006)E-4 erg/cm^2. The 1-sec peak photon flux measured
starting from T0+51.7 s in the 8-1000 keV band is 49 +/- 2 ph/s/cm^2.

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