MSSM Predictions of the neutral Higgs boson masses and LEP II production cross sections

Abstract

Within the framework of the Minimal Supersymmetric Standard Model (MSSM) the Higgs masses and LEP II production cross sections are calculated for a wide range of the parameter space. In addition, the parameter space restricted by unification, electroweak symmetry breaking and other low energy constraints is considered in detail, in which case the masses of all SUSY partners can be estimated, so that their contributions to the radiative corrections can be calculated. Explicit analytical formulae for these contribution are derived. The radiative corrections from the Yukawa couplings of the third generation are found to dominate over the contributions from charginos and neutralinos. Large Higgs mass uncertainties are due to the top mass uncertainty and the unknown sign of the Higgs mixing parameter. For the low tanb scenario the mass of the lightest Higgs is found to be below 103 GeV for a top mass below 190 GeV. The cross section at a LEP energy of 192 GeV is sufficient to find or exclude this low tanb scenario for a top mass below 180 GeV. For the high tanb scenario only a small fraction of the parameter space can be covered, since the Higgs mass is predicted between 105 and 125 GeV in most cases. At the theoretically possible LEP II energy of 205 GeV part of the parameter space for the large tanb scenario would be accessible.