Upper bounds of supersymmetric particle masses in a gaugino-originated radiative breaking scenario

The mass spectrum of supersymmetric particles is studied in the radiative breaking scenario of the minimal supersymmetric standard model, with an assumption that all soft supersymmetry-breaking parameters other than the gaugino masses are vanishing at the Planck scale. The U(1) gaugino mass M1X is taken to be an independent parameter, while the SU(2) and SU(3) gaugino masses are supposed to be unified. Within the ''natural'' range, the whole parameter space is scanned numerically and the consistent particle mass spectra with the experimental bounds are obtained. The supersymmetric particle masses are tightly bounded above as meR approx-lt 100 GeV, etc., if the top quark is sufficiently heavy mtop approx-gt 100 GeV and the minimal grand unified theory relation for three gaugino masses is satisfied. For a large |M1X|, there is no restriction other than the naturalness for the upper bounds of supersymmetric particle masses