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GCN Circular 15684

GRB 140104B: Fermi-LAT detection of a burst
2014-01-05T07:33:20Z (10 years ago)
Giacomo Vianello at SLAC <>
G. Vianello (Stanford University), J. McEnery (NASA/GSFC), and E.
Sonbas (Adiyaman Univ.), report on behalf of the Fermi-LAT team:

Starting at 17:32:03.15 on Jan. 4, 2014, Fermi LAT detected high
energy emission from GRB 140104B, which was also detected by Fermi-GBM
(trigger 410549526).

The best LAT on-ground location is found to be R.A., Dec 218.81, -8.90
deg (J2000) with an error radius of 0.22 deg (90% containment,
statistical error only), which was 25 deg from the LAT boresight at
the time of the trigger.

The data from the Fermi LAT show a significant increase in the event
rate within 10 deg of the GBM location after the GBM trigger that is
spatially and temporally correlated with the GBM emission with high
significance. The highest-energy photon is a 1.8 GeV event which is
observed ~800 seconds after the GBM trigger.

A Swift ToO has been requested for this burst.

The Fermi LAT point of contact for this burst is Eda Sonbas

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.

[GCP OPS NOTE(06jan14): Per author's request, name of the burst
in the subject line was corrected by removing the "731" ending.]
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