  We investigate the phase diagram in the temperature, imaginary chemical
potential plane for QCD with three degenerate quark flavors using Wilson type
fermions. While more expensive than the staggered fermions used in past studies
in this area, Wilson fermions can be used safely to simulate systems with three
quark flavors. In this talk, we focus on the (pseudo)critical line that extends
from $\mu=0$ in the imaginary chemical potential plane, trace it to the
Roberge-Weiss line, and determine its location relative to the Roberge-Weiss
transition point. In order to smoothly follow the (pseudo)critical line in this
plane we perform a multi-histogram reweighting in both temperature and chemical
potential. To perform reweighting in the chemical potential we use the
compression formula to compute the determinants exactly. Our results are
compatible with the standard scenario.
