  QCD with heavy dynamical quarks exhibits a first order thermal transition
which is driven by the spontaneous breaking of the global $\mathcal{Z}_3$
center symmetry. Decreasing the quark masses weakens the transition until the
corresponding latent heat vanishes at the critical mass. We explore the heavy
mass region with three flavors of staggered quarks and analyze the Polyakov
loop and its moments in a finite volume scaling study. We calculate the heavy
critical mass in the three flavor theory in the infinite volume limit for
$N_t=8$.
