Determination of the endpoint of the first order deconfiniement phase transition in the heavy quark region of QCD

Abstract

We study the endpoint of the first order deconfinement phase transition of 2 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 estimate the truncation error of the hopping parameter expansion, and discuss the lattice spacing dependence and the spatial volume dependence in the result of the critical point.

End point of the first-order phase transition of QCD in the heavy quark region by reweighting from quenched QCD

“…On our largest lattice, 36 3 × 6, however, we could not determine K ct due to the overlap problem. We reserve a study of the volume dependence for a future work [33,34]. Comparing the results for K ct calculated up to the leading and next-to-leading orders of the hopping parameter expansion, we found that the truncation error of the hopping parameter expansion is not small at N t = 6, while it is negligible at N t = 4.…”