Explicit CP violation of the Higgs sector in the next-to-minimal supersymmetric standard model

We study the explicit CP violation of the Higgs sector in the minimal supersymmetric standard model with a gauge singlet Higgs field. The magnitude of CP violation is discussed in the limiting cases of x much-gt v1,v2 and x much-lt v1, v2, where x and v1,2 denote the VEV's of singlet and doublet Higgs scalars, respectively. Our numerical predictions of the electric dipole moments of the electron and neutron lie around the present experimental upper limts. It is found that the large CP violation effect reduces the magnitude of the lightest Higgs boson mass on the order of a few tens of GeV