Speaker
Description
We study the endpoint of the first order deconfinement phase transition of two and 2+1 flavor QCD in the heavy quark region. We perform simulations of quenched QCD and apply the reweighting method to study the heavy quark region. The quark determinant for the reweighting is evaluated by a hopping parameter expansion. To reduce the overlap problem, we introduce an external source term of the Polyakov loop in the simulation. We study the location of critical point at which the first order phase transition changes to crossover by investigating the histogram of the Polyakov loop and applying the finite-size scaling analysis. We discuss the effect of the external source term on the overlap problem. We also evaluate the truncation error of the hopping parameter expansion, and study the lattice spacing dependence and the spatial volume dependence in the result of the critical point.
