CALCULABLE UPPER LIMIT ON THE MASS OF THE LIGHTEST HIGGS BOSON IN PERTURBATIVELY VALID SUPERSYMMETRIC THEORIES WITH ARBITRARY HIGGS SECTORS

We derive a calculable upper limit on the mass of the lightest Higgs boson in perturbatively valid supersymmetric theories with arbitrary Higgs sectors. We assume a supersymmetry spectrum around or below 1 TeV and the standard model gauge symmetry, but place no restrictions on the Higgs sector. We estimate m(h)0 < 146 GeV for M(t) greater than or similar to 100 GeV from all effects except possible additional heavy fermions beyond top (which could increase the limit approximately 12 GeV per extra family); for 60 less than or similar to M(t) less than or similar to 100 GeV we find m(h)0 < 156 GeV. In most explicitly constructed models the lightest Higgs boson mass does not saturate the upper limit.