Is a Light Gluino Compatible with N=1 Supersymmetry?

Abstract

Using the new CLEO bound on the branching ratio of the decay mode $b\longrightarrow s\gamma$ given by $1\times10^{-4}< B(b\longrightarrow s\gamma)<4\times10^{-4}$ at 95\% c.l., and the experimental bounds on the masses of the lightest chargino, the second lightest neutralino, and the light CP-odd Higgs, we find that a light gluino is incompatible with a class of supergravity models defined by $N=1$ supergravity, with a radiatively broken electroweak symmetry group and universality of scalar and gaugino masses at the unification scale. We also find in this scenario strong constraints on the parameter space due to the new CLEO bounds on $B(b\longrightarrow s\gamma)$. Presented in the International Workshop ``SUSY-94'', University of Michigan, Ann Arbor MI, May 14-17, 1994.