We study QCD with 2+1 flavors at nonzero temperature and nonzero chemical
potential. We present preliminary results obtained from lattice calculations
performed with an improved staggered fermions action (p4-action) on lattice
with temporal extent N_t = 4 on a line of constant physics with the strange
quark mass adjusted to its physical value and a pion mass of about 220 MeV. We
compute at imaginary chemical potential and compare with Taylor expansion
results. We focus our study on a range of temperatures 0.94 < T/T_c < 1.08.Comment: 7 pages, 12 figures, talk presented at the XXVIII International
Symposium on Lattice Field Theory (Lattice 2010), June 14-19, 2010,
Villasimius, Sardinia, Ital
