[vsnet-grb-info 16074] GRB 150127A: Fermi-LAT detection

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  17356
SUBJECT: GRB 150127A: Fermi-LAT detection
DATE:    15/01/28 02:05:36 GMT
FROM:    Judith Racusin at GSFC  <judith.racusin at nasa.gov>

J. L. Racusin (NASA/GSFC), G. Vianello (Stanford), and D. Kocevski 
(NASA/GSFC) report on behalf of the Fermi-LAT team:

At 09:32:44 on January 27, 2015, Fermi-LAT detected emission from 
GRB 150127A, which was also detected by Fermi-GBM (trigger 
444043967/150127398, GCN 17355).

The GBM location was initially inside the LAT field of view at an angle 
of ~39 degrees to the LAT boresight.  No significant excess is seen 
using standard analysis procedures >100 MeV.

Using the LAT Low Energy (LLE) data selection, over 60 counts 
above background were detected within a 10 s interval coinciding 
with the time of the GBM emission. This data selection has 
insufficient spatial resolution to provide a reliable LAT localization. 
Since an excess of events were not seen using the standard 
analysis selection, this detection is likely due to low energy 
gamma-rays (below 100 MeV).

The Fermi LAT point of contact for this burst is 
Judith Racusin (judith.racusin at nasa.gov).

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.