  We simulate one-flavor QCD with standard Wilson fermions at finite
temperature by the rational hybrid Monte Carlo algorithm. In the heavy quark
region when we decrease the quark mass there is an endpoint which terminates
the first order phase transition. We try to locate it by calculating the Binder
cumulant of the Polyakov loop norm. We estimate the end-point to be kappa_c
\sim 0.07-0.08.
