GCN Circular 17711

D. Kocevski (NASA/Goddard) and E. Bissaldi (INFN Bari) report on behalf of the Fermi-LAT team:

At 18:33:32 UT on April 15th, 2015, Fermi-LAT detected emission from GRB 150416A, which was also detected by Fermi-GBM (trigger 450902008/150416773).

The GBM location was initially outside the LAT field of view at an angle of ~68 degrees to the LAT boresight. Therefore, no observations of events > 100 MeV are available during the emission observed by the GBM.

Using the LAT Low Energy (LLE) data selection, over 25 counts above background were detected within a 50 s interval coinciding with the time of the GBM emission. This data selection has insufficient spatial resolution to provide a reliable LAT localization.

The Fermi-LAT point of contact for this burst is Elisabetta Bissaldi (elisabetta.bissaldi@ba.infn.it<mailto:elisabetta.bissaldi@ba.infn.it>).

The Fermi-LAT is a pair conversion telescope designed to cover the energy band from 20 MeV to greater than 300 GeV. It is the product of an international collaboration between NASA and DOE in the U.S. and many scientific institutions across France, Italy, Japan and Sweden.