  We investigate the phase structure of 3-flavor QCD in the presence of finite
quark chemical potential by using Wilson-Clover fermions. To deal with the
complex action with finite density, we adopt the phase reweighting method. In
order to survey a wide parameter region, we employ the multi-parameter
reweighting method as well as the multi-ensemble reweighting method.
Especially, we focus on locating the critical end point that characterizes the
phase structure. It is estimated by the kurtosis intersection method for the
quark condensate. For Wilson-type fermions, the correspondence between bare
parameters and physical parameters is indirect, thus we present a strategy to
transfer the bare parameter phase structure to the physical one. We conclude
that the curvature with respect to the chemical potential is positive. This
implies that, if one starts from a quark mass in the region of crossover at
zero chemical potential, one would encounter a first-order phase transition
when one raises the chemical potential.
