Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Search for GeV gamma ray burst signal in the field of view of muon
  telescopes   We present a search for the muon excess associated in time (preceding or
following) with the trigger of gamma ray burst (GRB) detected by the satellite
borne instruments. The 1 Hz rate data was collected at the sea level in the
area located at 22S and 43W, inside the South Atlantic Anomaly (SAA) region and
close to its center. Using 1 sec amd 10 sec time binning, we found the muon
excess with significance $>5\sigma$ associated with the gamma ray burst
GRB091112 observed by Swift BAT, Fermi GBM and Suzaku-WAM satellites. The
detected muon time profile shows a rough peak at $\sim T+223$ sec
($5.2\sigma$), and with a duration of 7 sec. The FLUKA Monte Carlo simulation
of the photon-to-muon conversion in the atmosphere shows that the observed muon
excess can be explained by progenitor photons with energies above 10 GeV. This
energy value is above the limits expected from the maximum synchrotron emission
combined with the shock wave evolution. It shows constrains on the external
shock synchrotron model for GRB emission in the GeV energy band and favors
scenarios with overall afterglow spectrum, ranging from the optical-to-GeV
photons. On the basis of the observed associations with the satellite data, we
report confidence analysis of the background fluctuations and fluencies in the
GeV energy region, that is important for better understanding of the GRB
physics.

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The categories of this paper are: atom-ph
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The categories of this paper are: comp-gas
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The categories of this paper are: dg-ga
2
The categories of this paper are: math
11
The categories of this paper are: hep-lat
25
The categories of this paper are: patt-sol
8
The categories of this paper are: hep-ex
14
The categories of this paper are: math-ph
19
The categories of this paper are: eess
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The categories of this paper are: q-fin
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The categories of this paper are: adap-org
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The categories of this paper are: funct-an
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The categories of this paper are: nlin
0
The categories of this paper are: hep-ph
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The categories of this paper are: q-alg
5
The categories of this paper are: gr-qc