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GCN Circular 8183

GRB080825C: Fermi-LAT observations
2008-09-05T17:45:46Z (16 years ago)
Aurelien Bouvier at Stanford <>
A. Bouvier (SLAC), D. Band (GSFC), J. Bregeon (INFN Pisa), J. Chiang  
(SLAC), S. Cutini (ASDC), B. Dingus (LANL), N. Gehrels (GSFC), Y.  
Fukazawa (Hiroshima U), M. Hayashida (SLAC), F. Longo (INFN Trieste),  
J. McEnery (GSFC), M. Ohno (JAXA), N. Omodei (INFN Pisa), V. Pelassa  
(LPTA), F. Piron (LPTA), D. Sanchez (LLR), J. Scargle (NASA Ames), H.  
Tajima (SLAC), T. Tanaka (SLAC), G. Thayer (SLAC) on behalf of the  
Fermi LAT team:

We report a detection by the Fermi Large Area Telescope (LAT) of  
emission from GRB080825C, which was triggered by the Fermi Gamma-ray  
Burst Monitor (GBM) at 14:13:48 UT on August 25th 2008 (GCN 8141 by  
Van der Horst et al.). The angle of the GBM best localization (ra,  
dec=232.2,-4.6) with the LAT boresight was 60 deg at the time of the  
trigger which is on the edge of our field of view.

The data from the Fermi LAT shows a significant increase in the event  
rate within 10 degree of the GBM localization and up to 35 seconds  
after the GBM trigger that is spatially and temporally correlated  
with the GBM emission with a significance of more than 5 sigma. All  
the LAT events detected during the GBM emission have energies below 1  

The best LAT on-ground localization is found to be  
RA,DEC=233.96,-4.72 deg with a 90% containment radius of 1.5 deg  
(statistical+systematics; 68% containment radius: 0.95 deg) which is  
consistent with the GBM localization.

This circular is an official product of the Fermi LAT team.
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