PUB - Publikationen an der Universität Bielefeld

We investigate $U_A(1)$ breaking above $T_c$ in terms of the Dirac spectrumon configurations with (2+1)-flavors, using the HISQ action. The strange quarkmass is at its physical value. We use several light quark masses correspondingto the Goldstone pion masses in the range of about 115 -- 230 MeV on latticesof size 32$^3 \times$8 and 48$^3 \times$8. We calculate the 100 lowest-lyingDirac eigenvalues at temperatures below and above $T_c$. We investigate thevolume dependence of the Dirac eigenvalue density to determine whether there isa gap around zero, which can appear if $U_A(1)$ symmetry is restored in thechiral symmetric phase. We also investigate the quark mass dependence of theDirac eigenvalue density at zero and check whether there is a linear behaviorthat would signal the $U_A(1)$ breaking above $T_c$.