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arXiv · 0802.3979

The diagonal and off-diagonal quark number susceptibility of high temperature and finite density QCD

Ari Hietanen·Kari Rummukainen
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Abstract

We study the quark number susceptibility of the hot quark-gluon plasma at zero and non-zero quark number density, using lattice Monte Carlo simulations of an effective theory of QCD, electrostatic QCD (EQCD). Analytic continuation is used to obtain results at non-zero quark chemical potential. We measure both flavor singlet (diagonal) and non-singlet (off-diagonal) quark number susceptibilities. The diagonal susceptibility approaches the perturbative result above 20T_c, but below that temperature we observe significant deviations. The results agree well with 4d lattice data down to temperatures 2T_c. The off-diagonal susceptibility is more prone to statistical and systematic errors, but the results are consistent with perturbation theory already at 10T_c.

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Ari Hietanen, Kari Rummukainen. 2008-04-29. The diagonal and off-diagonal quark number susceptibility of high temperature and finite density QCD. https://doi.org/10.1088/1126-6708%2F2008%2F04%2F078

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