@article{oai:niigata-u.repo.nii.ac.jp:00002302, author = {Ejiri, S. and Karsch, F. and Laermann, E. and Schmidt, C.}, issue = {5}, journal = {Physical Review D, Physical Review D}, month = {Mar}, note = {Using Taylor expansions of the pressure obtained previously in studies of 2-flavor QCD at nonzero chemical potential we calculate expansion coefficients for the energy and entropy densities up to O(μ 6 q ) in the quark chemical potential. We use these series in μ q /T to determine lines of constant entropy per baryon number (S/N B ) that characterize the expansion of dense matter created in heavy ion collisions. In the high temperature regime these lines are found to be well approximated by lines of constant μ q /T . In the low temperature phase, however, the quark chemical potential is found to increase with decreasing temperature. This is in accordance with resonance gas model calculations. Along the lines of constant S/N B we calculate the energy density and pressure. Within the accuracy of our present analysis we find that the ratio p/ϵ for T>T 0 as well as the softest point of the equation of state, (p/ϵ) min ≃0.075 , show no significant dependence on S/N B.}, title = {Isentropic equation of state of 2-flavor QCD}, volume = {73}, year = {2006} }