The Higgs sector in the next-to-MSSM

We study the Higgs sector in the next-to-minimal supersymmetric standard model both with and without explicit CP violation, focusing on the case of a weak-scale expectation value of the singlet field. We scan a wide range of the parameter space to determine allowed regions by requiring that the electroweak vacuum be the global minimum of the effective potential and that, the neutral Higgs bosons with moderate gauge coupling be heavier than the lower bound on the Higgs boson in the standard model. Among the allowed sets of parameter values, some sets yield the situation in which the light Higgs bosons couple with the Z boson too weakly for observation to be possible in present collider experiments. For such parameter sets, we determine an upper bound on the charged Higgs mass that is attainable in LHC.