The Higgs mass in the MSSM infrared fixed point scenario Original Research Article

In the infrared fixed point (IFP) scenario of the minimal supersymmetric model (MSSM), the top-quark mass and other physical quantities of the low-energy theory are insensitive to the values of the parameters of the theory at some high energy scale. In this framework we evaluate the light CP-even Higgs mass, mh0, taking into account some important effects that had not been previously considered. In particular, the supersymmetric correction to the relation between the running and the physical top-quark masses lowers the value of tan β, thereby implying a lower predicted value of mh0. Assuming a supersymmetric threshold of MS ⩽ 1 TeV and Mt = 175 GeV, we find an upper bound of mh0 ⩽ 97 ± 2 GeV; the most plausible value of mho lies somewhat below the upper bound. This places the Higgs boson in the IFP scenario well within the reach of the LEP-2 Higgs search.