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arXiv · hep-ph/0212283

Quark number susceptibilities of hot QCD up to g^6ln(g)

Abstract

The pressure of hot QCD has recently been determined to the last perturbatively computable order g^6 ln(g) by Kajantie et al. using three-dimensional effective theories. A similar method is applied here to the pressure in the presence of small but non-vanishing quark chemical potentials, and the result is used to derive the quark number susceptibilities in the limit mu = 0. The diagonal quark number susceptibility of QCD with n_f flavours of massless quarks is evaluated to order g^6ln(g) and compared with recent lattice simulations. It is observed that the results qualitatively resemble the lattice ones, and that when combined with the fully perturbative but yet undetermined g^6 term they may well explain the behaviour of the lattice data for a wide range of temperatures.

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BibTeXRIS

A. Vuorinen. 2003-03-11. Quark number susceptibilities of hot QCD up to g^6ln(g). https://doi.org/10.1103/physrevd.67.074032

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