Towards finite density QCD with Taylor expansions

Frithjof Karsch, Bernd-Jochen Schaefer, Mathias Wagner, Jochen Wambach

Published 2010-09-27, updated 2011-03-09Version 2

Convergence properties of Taylor expansions of observables, which are also used in lattice QCD calculations at non-zero chemical potential, are analyzed in an effective N_f = 2+1 flavor Polyakov-quark-meson model. A recently developed algorithmic technique allows the calculation of higher-order Taylor expansion coefficients in functional approaches. This novel technique is for the first time applied to an effective N_f = 2+1 flavor Polyakov-quark-meson model and the findings are compared with the full model solution at finite densities. The results are used to discuss prospects for locating the QCD phase boundary and a possible critical endpoint in the phase diagram.