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Charge Fluctuations along the QCD phase boundary

K. Redlich·B. Friman·C. Sasaki
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Abstract

We discuss the properties of the net--quark and isovector fluctuations along the chiral phase transition line in the plane spanned by temperature and baryon chemical potential. Our results are obtained in terms of the Nambu--Jona-Lasinio (NJL) model within the mean-field approximation. The model is formulated at the finite temperature and for non-vanishing net--quark and the isospin chemical potentials. The fermion interactions are controlled by the strength of the scalar and vector couplings in the iso-scalar and iso-vector channels of constituent quarks. We explore properties and differences in the behavior of the net--quark number and isovector susceptibilities for different values of thermal parameters near the phase transition. We argue that any non-monotonic behavior of the net--quark number susceptibility along the phase transition boundary is an excellent probe of the existence and the position of the second order endpoint in the QCD phase diagram.

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K. Redlich, B. Friman, C. Sasaki. 2006-09-20. Charge Fluctuations along the QCD phase boundary. https://doi.org/10.1088/0954-3899%2F32%2F12%2Fs35

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