Abstract
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 in the quark chemical potential. We use these series in to determine lines of constant entropy per baryon number () 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 . 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 we calculate the energy density and pressure. Within the accuracy of our present analysis we find that the ratio for as well as the softest point of the equation of state, , show no significant dependence on .
- Received 27 December 2005
DOI:https://doi.org/10.1103/PhysRevD.73.054506
©2006 American Physical Society