EXPERIMENTAL ASPECTS OF SU(5)XU(1) SUPERGRAVITY

We study various aspects of SU(5) X U(1) supergravity as they relate to the experimental verification or falsification of this model. We consider two string-inspired, universal, one-parameter, no-scale soft-supersymmetry-breaking scenarios, driven by the F terms of the moduli and dilaton fields. The model is described in terms of the supersymmetry mass scale (i.e., the chargino mass m(chi1+/-)), tanbeta, and the top-quark mass. We first determine the combined effect on the parameter space of all presently available direct and indirect experimental constraints, including the CERN LEP lower bounds on sparticle and Higgs-boson masses, the b-->sgamma rate, the anomalous magnetic moment of the muon, the high-precision electroweak parameters epsilon1,epsilon(b) (which imply m(t) less than or similar 180 GeV), and the muon fluxes in underground detectors (neutrino telescopes). For the still-allowed points in (m(chi1)+/-, tanbeta) parameter space, we reevaluate the experimental situation at the Fermilab Tevatron, LEP II, and DESY HERA. In the 1994 run, the Tevatron could probe chargino masses as high as 100 GeV. At LEP II the parameter space could be explored with probes of different resolutions: Higgs-boson searches, selectron searches, and chargino searches. Moreover, for m(t) less than or similar 150 GeV, these Higgs-boson searches could explore all of the allowed parameter space with square-root s less than or similar 210 GeV.