Supersymmetry reach of Fermilab Tevatron upgrades:: The large tan β case -: art. no. 075008

The Yukawa couplings of the tau lepton and the bottom quark become comparable to, or even exceed, electroweak gauge couplings for large values of the supersymmetry parameter tan beta. As a result, the lightest tau slepton <(tau)over tilde>(1) and bottom squark (b) over tilde(1) can be significantly lighter than corresponding sleptons and squarks of the first two generations. Gluino, chargino, and neutralino decays to third generation particles are significantly enhanced when tan beta is large. This affects projections for collider experiment reach for supersymmetric particles. In this paper, we evaluate the reach of the Fermilab Tevatron p (p) over bar collider for supersymmetric signals in the framework of the minimal supergravity model. We find that the reach via signatures with multiple isolated leptons (e and mu) is considerably reduced. For very large tan beta, the greatest reach is attained in the multijet+E-T(miss) signature. Some significant extra regions may be probed by requiring the presence of an identified b jet in jets+E-T(miss) events, or by requiring one of the identified leptons in clean trilepton events to actually be a hadronic 1 or 3 charged prong tau. In an appendix, we present formulas for chargino, neutralino, and gluino three body decays which are valid at large tan beta. [S0556-2821(98)02119-5].