The absolute upper bound on the 1-loop corrected mass of the lightest scalar Higgs boson in the next-to-minimal supersymmetric standard model

We examine in detail radiative corrections to the lightest scalar Higgs boson mass due to the top-quark and top-scalar-quark loops in the next-to-minimal supersymmetric standard model (NMSSM). In our analysis, the mass matrix of the top-scalar-quark contains terms proportional to the gauge couplings. Therefore, our formula for the scalar Higgs boson mass matrix at the 1-loop level partially includes the gauge boson contributions. Thus we calculate the upper bound on the lightest scalar Higgs boson mass without the gauge terms as well as with the gauge terms in the top-scalar-quark masses. The upper bound on the lightest scalar Higgs boson mass can be increased by about 20 GeV by the inclusion of terms proportional to the gauge couplings in the top-scalar-quark masses. We find that the absolute upper bound on the 1-loop corrected mass of the lightest scalar Higgs boson partially including the gauge boson contributions is about 156 GeV.