Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Neutral Pion Decay Width in a Hot and Dense Medium   We study the behavior of the $\pi^0$ width as a function of temperature and
density. We provide simple expressions for the neutral pion width in a hot and
dense medium based on a renormalized version of the microscopic Nambu Jona
Lasinio model. Then we consider the two cases where the pion mass is finite or
vanishes at the critical temperature and discuss the phenomenological
consequences of both cases.

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The categories of this paper are: gr-qc
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The categories of this paper are: patt-sol
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The categories of this paper are: mtrl-th
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The categories of this paper are: acc-phys
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The categories of this paper are: nucl-th
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The categories of this paper are: solv-int
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The categories of this paper are: q-bio
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The categories of this paper are: adap-org
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The categories of this paper are: atom-ph
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The categories of this paper are: chem-ph
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The categories of this paper are: physics
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The categories of this paper are: nlin
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The categories of this paper are: supr-con
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The categories of this paper are: astro-ph
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The categories of this paper are: hep-th
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The categories of this paper are: quant-ph