出版社：SISSA, Scuola Internazionale Superiore di Studi Avanzati
摘要：We study the equation of state in two-flavor QCD at finite temperature and density. Simulations
are made with the RG-improved gluon action and the clover-improved Wilson quark action.
Along the lines of constant physics for mPS/mV = 0.65 and 0.80, we compute the derivatives of
the quark determinant with respect to the quark chemical potential μq up to the fourth order at
μq = 0. We adopt several improvement techniques in the evaluation. We study thermodynamic
quantities and quark number susceptibilities at finite μq using these derivatives. We find enhancement
of the quark number susceptibility at finite μq, in accordance with previous observations
using staggered-type quarks. This suggests the existence of a nearby critical point.
