  We present results for the phase diagram of three flavor QCD for \mu_B ~ 500
MeV. Our simulations are performed with imaginary chemical potential \mu_I for
which the fermion determinant is positive. Physical observables are then fitted
by truncated Taylor series and continued to real chemical potential. We map out
the location of the critical line T_c(\mu_B) with an accuracy up to terms of
order (\mu_B/T)^6. We also give first results on a determination of the
critical endpoint of the transition and its quark mass dependence. Our results
for the endpoint differ significantly from those obtained by other methods, and
we discuss possible reasons for this.
