  I present the highlights of a recent study of the effective QCD phase diagram
on the temperature T and quark chemical potential mu plane, where the strong
interactions are modeled using the linear sigma model coupled to quarks. The
phase transition line is found from the effective potential at finite T and mu
taking into account the plasma screening effects. We find the location of the
critical end point (CEP) to be (mu^CEP/T_c,T^CEP/T_c) \sim (1.2,0.8), where T_c
is the (pseudo)critical temperature for the crossover phase transition at
vanishing mu. This location lies within the region found by lattice inspired
calculations. Since the linear sigma model does not exhibit confinement, I
argue that the location is due to the proper treatment of the plasma screening
effects and not to the size of the confining scale. I also comment on the
extension of this study to determine the dependence of the CEP's location on
the strength of an external magnetic field.
