Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Dileptons and Chiral Symmetry Restoration   We report on recent work relating the medium effects observed in dilepton
spectra in heavy-ion collisions to potential signals of chiral symmetry
restoration. The key connection remains the approach to spectral function
degeneracy between the vector-isovector channel with its chiral partner, the
axialvector-isovector channel. Several approaches are discussed to elaborate
this connection, namely QCD and Weinberg sum rules with input for chiral order
parameters from lattice QCD, and chiral hadronic theory to directly evaluate
the medium effects of the axialvector channel and the pertinent pion decay
constant as function of temperature. A pattern emerges where the chiral mass
splitting between rho and a_1 burns off and is accompanied by a strong
broadening of the spectral distributions.

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The categories of this paper are: plasm-ph
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The categories of this paper are: chem-ph
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The categories of this paper are: funct-an
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The categories of this paper are: acc-phys
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The categories of this paper are: atom-ph
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The categories of this paper are: physics
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The categories of this paper are: hep-lat
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The categories of this paper are: nucl-ex
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The categories of this paper are: q-fin
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The categories of this paper are: math-ph
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The categories of this paper are: nlin
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The categories of this paper are: dg-ga
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The categories of this paper are: patt-sol
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The categories of this paper are: chao-dyn
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The categories of this paper are: supr-con
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The categories of this paper are: astro-ph