QCD phase diagram for small densities from simulations at imaginary μ

Abstract

We present results on the QCD phase diagram for small densities without reweighting. Our simulations are performed with an imaginary chemical potential μ I for which the fermion determinant is positive. On an 8 3 × 4 lattice with 2 flavors of staggered quarks, we map out the pseudo-critical temperature T c (μ I) . For μ I/T ≤ π/3 , this is an analytic function whose Taylor expansion converges rapidly, with truncation errors smaller than statistical ones. The result is analytically continued to give the location of the pseudo-critical line for real μ B ≲ 500 MeV.