PRECISE PREDICTION FOR THE MASS OF THE LIGHTEST HIGGS-BOSON IN THE MSSM

The leading diagrammatic two-loop corrections are incorporated into th e prediction for the mass of the lightest Higgs boson, m(h). in the Mi nimal Supersymmetric Standard Model (MSSM). The results, containing th e complete diagrammatic one-loop corrections, the new two-loop result and refinement terms incorporating leading electroweak two-loop and hi gher-order QCD contributions, are discussed and compared with results obtained by renormalization group calculations. Good agreement is foun d in the case of vanishing mixing in the scalar quark sector, while si zable deviations occur if squark mixing is taken into account. (C) 199 8 Elsevier Science B.V. All rights reserved.