Absolute Upper Bound on the 1-loop Corrected mass of S₁ in the NMSSM

We examine in detail radiative corrections to the lightest scalar Higgs boson mass due to the top quark and scalar quark loops in the next-to-minimal supersymmetric standard model (NMSSM). We take into account the nondegenerate state for the top scalar quark masses. In our analysis, the mass matrix of the top scalar quark contains the gauge terms. Therefore our formula for the scalar Higgs boson mass matrix at the 1-loop level includes the contribution of the gauge sector as well as the effect of the top scalar quark mass splitting. Thus we calculate the upper bound on the lightest scalar Higgs boson mass using our formula. We find that the absolute upper bound on the 1-loop corrected mass of the lightest scalar Higgs boson is about 156 GeV.