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 8495

GRB 081105B: Fermi GBM detection
2008-11-07T17:01:51Z (16 years ago)
Andreas von Kienlin at MPE <>
Elisabetta Bissaldi (MPE) and A. von Kienlin (MPE) 
report on behalf of the Fermi GBM Team: 

"At 14:43:51.29 UT on 05 November 2008, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 081105B (trigger 247589032 / 081105614).
The on-ground calculated location, using the GBM trigger 
data, is RA = 215.7 deg, Dec = 42.8 (J2000 degrees, 
equivalent to 14h 23m, 42d 48'), with an uncertainty 
of 12 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 87 degrees.

This short GRB consists of a single peak with an estimated
T90 (8-1000 keV) of 180 ms and T50 (8-1000 keV) of 64 ms.
The spectral fit to this weak event is poorly constrained.
A fit of the time-averaged spectrum from T0-0.067 s to T0-0.019 s  
by a simple power law function yields an index of -1.17 +/- 0.05 
(chi squared 311 for 421 d.o.f.).
The event fluence (8-1000 keV) in this time interval is 
(2.28 +/- 0.11)E-07 erg/cm^2. The photon flux on the 
16 ms timescale measured starting from T0-0.067 s 
in the 8-1000 keV band is 20 +/- 3 ph/s/cm^2. 

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