出版社：SISSA, Scuola Internazionale Superiore di Studi Avanzati
摘要：We propose a method to probe the nature of phase transitions in lattice QCD at finite temperature
and density, which is based on the investigation of an effective potential as a function of the average
plaquette. We analyze data obtained in a simulation of two-flavor QCD using p4-improved
staggered quarks with bare quark mass m=T 0:4, and find that a first order phase transition line
appears in the high density regime for mq=T >2:5. The effective potential as a function of the
quark number density is also studied. We calculate the chemical potential as a function of the
density from the canonical partition function and discuss the existence of the first order phase
transition line.
