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arXiv · 1212.4200

Thermal Correlators in the ρ channel of two-flavor QCD

Bastian B. Brandt·Anthony Francis·Harvey B. Meyer·Hartmut Wittig
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Abstract

We present a lattice QCD calculation with two dynamical flavors of the isovector vector correlator in the high-temperature phase. We analyze the correlator in terms of the associated spectral function, for which we review the theoretical expectations. In our main analysis, we perform a fit for the difference of the thermal and vacuum spectral functions, and we use an exact sum rule that constrains this difference. We also perform a direct fit for the thermal spectral function, and obtain good agreement between the two analyses for frequencies below the two-pion threshold. Under the assumption that the spectral function is smooth in that region, we give an estimate of the electrical conductivity.

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Bastian B. Brandt, Anthony Francis, Harvey B. Meyer, Hartmut Wittig. 2012-12-18. Thermal Correlators in the ρ channel of two-flavor QCD. https://doi.org/10.1007/jhep03(2013)100

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