PUB - Publikationen an der Universität Bielefeld

We study scaling behavior of a chiral order parameter in the low densityregion, performing a simulation of two-flavor QCD with improved Wilson quarks.The scaling behavior of the chiral order parameter defined by a Ward-Takahashiidentity agrees with the scaling function of the three-dimensional O(4) spinmodel at zero chemical potential. We extend the scaling study to finite densityQCD. Applying the reweighting method and calculating derivatives of the chiralorder parameter with respect to the chemical potential, the scaling propertiesof the chiral phase transition are discussed in the low density region. Wemoreover calculate the curvature of the phase boundary of the chiral phasetransition in the temperature and chemical potential plane assuming the O(4)scaling relation.