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arXiv · 1210.2588

Rho-meson resonance broadening in QCD at finite temperature

Abstract

Thermal Finite Energy QCD sum rules for the vector current correlator are used to study quark-gluon deconfinement. Assuming $ρ$-meson saturation of the correlator in the hadronic sector, and the Operator Product Expansion in QCD, we obtain the temperature behavior of the resonance parameters (coupling, mass, and width), and of the leading vacuum condensates, as well as the perturbative QCD threshold in the complex squared energy plane. The results are consistent with quark-gluon deconfinement at a critical temperature $T_c \simeq 197 MeV$. The temperature dependence of the $ρ$-meson width is of importance for current experiments on dimuon production in nuclear collisions.

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Alejandro Ayala, C. A. Dominguez, M. Loewe, Y. Zhang. 2012-12-10. Rho-meson resonance broadening in QCD at finite temperature. https://doi.org/10.1103/physrevd.86.114036

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