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arXiv · 1004.1059

Vector mesons at finite temperature and QCD sum rules

Youngshin Kwon·Chihiro Sasaki·Wolfram Weise
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Abstract

Finite energy sum rules for vector and axial-vector currents are derived in a thermal medium to provide constraints for the spectral behavior of rho and a1 mesons at nonvanishing temperature and hence to study the tendency toward chiral symmetry restoration. The parity-mixing ansatz for the rho and a1 spectra, including finite widths, is investigated as a function of temperature. Characteristic differences between vector and axial-vector channels are discussed with regard to the implementation of the chiral-symmetry-breaking scale, 4pi times the pion decay constant, in the sum rule approach.

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Youngshin Kwon, Chihiro Sasaki, Wolfram Weise. 2010-06-04. Vector mesons at finite temperature and QCD sum rules. https://doi.org/10.1103/physrevc.81.065203

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