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Abstract:

We analyze a class of supersymmetric models first introduced by Arkani-Hamed et al and Borzumati et al in which the light neutrino masses result from higher-dimensional supersymmetry-breaking terms in the MSSM super- and Kahler-potentials. The mechanism is closely related to the Giudice-Masiero mechanism for the MSSM $μ$ parameter, and leads to TeV-scale right-handed neutrino and sneutrino states, that are in principle accessible to direct experimental study. The dominant contribution to the light neutrino (Majorana) mass matrix is a one-loop term induced by a lepton-number violating $B$-term for the sneutrino states that is naturally present. We focus upon the simplification and analysis of the flavour structure of this general class of models, finding that simple and novel origins for the light neutrino mass matrix are possible. We find that a subdominant tree-level `see-saw' contribution may lead to interesting perturbations of the leading one-loop-induced flavour structure, possibly generating the small ratio $Δm_{\rm solar}^2/Δm_{\rm atm}^2$ dynamically.

Abstract:

The search for pair production of scalar top quarks in an R-parity violating supersymmetry scenario in 106 pb-f of pp̄ collisions at √s = 1.8 TeV collected by the Collider Detector at Fermilab was discussed. It was found that in this mode each t1̃ decayed into a τ lepton and a b quark. The events with two τ's, one decaying leptonically and one decaying hadronically and two jets were searched. It was observed that a 95% confidence level lower limit was set on the t 1̄ mass at 122 GeV/c2 for Br(t1̃ → τb).