  A hybrid parameterization of a quasiparticle equation of state is proposed,
with a critical point implemented phenomenologically. On the one hand, a
quasiparticle model with finite chemical potential is employed for the
quark-gluon plasma phase, calibrated to the lattice quantum chromodynamics
data. On the other hand, the low-temperature region for the hadronic phase of
the matter is described by the hadronic resonance gas model with excluded
volume correction. A particular interpolation scheme is adopted so that the
phase transition is a smooth crossover for small chemical potential. A
phenomenological critical pointed is implemented beyond which the phase
transition becomes that of the first order.
