Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The structure of TeV-bright shell-type supernova remnants   Aims. Two-dimensional MHD simulations are used to model the emission
properties of TeV-bright shell-type supernova remnants (SNRs) and to explore
their nature. Methods. In the leptonic scenario for the TeV emission, the
$\gamma$-ray emission is produced via Inverse Compton scattering of background
soft photons by high-energy electrons accelerated by the shocks of the SNRs.
The TeV emissivity is proportional to the magnetic field energy density and MHD
simulations can be used to model the TeV structure of such remnants directly.
2D MHD simulations for SNRs are then performed under the assumption that the
ambient interstellar medium is turbulent with the magnetic field and density
fluctuations following a Kolmogorov-like power-law spectrum. Results. (1) As
expected, these simulations confirm early 1D and 2D modelings of these sources,
namely the hydrodynamical evolution of the shock waves and amplification of
magnetic field by Rayleigh-Taylor convective flows and by shocks propagating in
a turbulent medium; (2) We reproduce rather complex morphological structure for
$\gamma$-rays, suggesting intrinsic variations of the source morphology not
related to the structure of the progenitor and environment; (3)The observed
radial profile of several remnants are well reproduced with an ambient medium
density of $0.1-1$ cm$^{-3}$. An even lower ambient density leads to a sharper
drop of the TeV brightness with radius than what is observed near the outer
edge of these remnants. Conclusions. In a turbulent background medium, we can
reproduce the observed characteristics of several shell-type TeV SNRs with
reasonable parameters except for a higher ambient density than that inferred
from X-ray observations.

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The categories of this paper are: adap-org
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The categories of this paper are: chao-dyn
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The categories of this paper are: plasm-ph
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The categories of this paper are: hep-lat
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The categories of this paper are: math
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The categories of this paper are: chem-ph
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The categories of this paper are: hep-ex
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The categories of this paper are: solv-int
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The categories of this paper are: math-ph
3
The categories of this paper are: physics
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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: cs
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The categories of this paper are: comp-gas
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The categories of this paper are: funct-an
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The categories of this paper are: econ