Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Modeling the high-energy emission in GRB 110721A and implications on the
  early multiwavelength and polarimetric observations   GRB 110721A was detected by the Gamma-ray Burst Monitor and the Large Area
Telescope (LAT) onboard the Fermi satellite and the Gamma-ray Burst Polarimeter
onboard the IKAROS solar mission. Previous analysis done of this burst showed:
i) a linear polarization signal with position angle stable ($\phi_p=
160^\circ\pm11$) and high degree of $\Pi=84^{+16}_{-28}$, ii) an extreme peak
energy of a record-breaking at 15$\pm$2 MeV, and iii) a subdominant prompt
thermal component observed right after the onset of this burst. In this paper,
the LAT data around the reported position of GRB 110721A are analysed with the
most recent software and then, the LAT light curve above 100 MeV was obtained.
The LAT light curve is modelled in terms of adiabatic early-afterglow external
shocks when the outflow propagates into a stellar wind. Additionally, we
discuss the possible origins and also study the implications of the
early-afterglow external shocks on the extreme peak energy observed at 15$\pm$2
MeV, the polarization observations and the subdominant prompt thermal
component.

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The categories of this paper are: physics
2
The categories of this paper are: math
1
The categories of this paper are: cs
25
The categories of this paper are: patt-sol
15
The categories of this paper are: nucl-ex
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The categories of this paper are: econ
31
The categories of this paper are: ao-sci
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The categories of this paper are: nlin
28
The categories of this paper are: alg-geom
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The categories of this paper are: stat
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The categories of this paper are: hep-lat
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The categories of this paper are: dg-ga
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The categories of this paper are: nucl-th
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The categories of this paper are: mtrl-th
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The categories of this paper are: atom-ph
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The categories of this paper are: chem-ph