Skip to main content
Testing. You are viewing the public testing version of GCN. For the production version, go to
New Announcement Feature, Code of Conduct, Circular Revisions. See news and announcements

GCN Circular 8498

GRB 081024C: Fermi Gamma-ray Burst Monitor detection
2008-11-07T20:34:54Z (16 years ago)
Valerie Connaughton at MSFC <>
Valerie Connaughton (UAH) reports on behalf of the Fermi GBM Team:

"At 20:25:34 UT on 24 October 2008, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 081024C (trigger 246572735 / 081024851).

The on-ground calculated location, using the GBM trigger
data, is RA = 147.6, DEC = -8.2 (J2000 degrees, equivalent to 09h50m,
 -08d12'), with an uncertainty of 3.2 degrees (radius, 1-sigma containment,
statistical only; there is additionally a systematic error which is 
estimated to be 2 to 3 degrees).  The angle from the Fermi LAT boresight
is 78 degrees.

The GBM light curve consists of a single weak peak with some
substructure, lasting about 65 seconds.
The time-averaged spectrum from T0-8 s to T0+57 s is best fit by
a Band function with Epeak = 65 +/- 7 keV,
alpha = -0.6 +/- 0.2, and beta = -2.5 +/- 0.2
(chi squared 358 for 355 d.o.f.)

The event fluence (50 -- 300 keV) in this time interval is
(4.0 +/- 0.9)E-6 erg/cm^2, and its 1-second peak flux in the same
energy range is approximately 1 ph/cm^2/sec.

The spectral analysis results presented above are preliminary;
final results will be published in the GBM GRB Catalog."
Looking for U.S. government information and services? Visit