Phase structure of lattice QCD with two flavors of Wilson quarks at finite temperature and chemical potential

We present results for phase structure of lattice QCD with two degenerate flavors (Nf=2) of Wilson quarks at finite temperature T and small baryon chemical potential μB. Using the imaginary chemical potential for which the fermion determinant is positive, we perform simulations at points where the ratios of pseudoscalar meson mass to the vector meson mass m_π/m_ρ are between 0.943(3) and 0.899(4) as well as in the quenched limit. By analytic continuation to real quark chemical potential μ, we obtain the transition temperature as a function of small μB. We attempt to determine the nature of transition at imaginary chemical potential by histogram, Monte Carlo (MC) history, and finite size scaling. In the infinite heavy quark limit, the transition is of first order. At intermediate values of quark mass mq corresponding to the ratio of m_π/m_ρ in the range from 0.943(3) to 0.899(4) at aμI=0.24, the MC simulations show the absence of phase transition.