Probing R-parity violating models of neutrino mass at the Tevatron via top Squark decays

We have estimated the limiting branching ratio of the R-parity violating (RPV) decay of the lighter top squark, t̃1 → ld (l = e or μ and d is a down type quark of any flavor), as a function of top squark mass(mt̃1) for an observable signal in the di-lepton plus di-jet channel at the Tevatron RUN-II experiment with 2 fb luminosity. Our simulations indicate that the lepton number violating nature of the underlying decay dynamics can be confirmed via the reconstruction of mt̃1 . The above decay is interesting in the context of RPV models of neutrino mass where the RPV couplings (λ′i3j) driving the above decay are constrained to be small ( ∼ 10−3−10−4). If t̃1 is the next lightest super particle a theoretically well motivated scenario then the RPV decay can naturally compete with the Rparity conserving (RPC) modes which also have suppressed widths. The model independent limiting BR can delineate the parameter space in specific supersymmetric models, where the dominating RPV decay is observable and predict the minimum magnitude of the RPV coupling that will be sensitive to Run-II data. We have found it to be in the same ballpark value required by models of neutrino mass, for a wide range of mt̃1 . A comprehensive future strategy for linking top squark decays with models of neutrino mass is sketched. PACS numbers: 11.30.Pb, 13.85.-t, 14.60.Pq, 14.80.Ly [email protected] [email protected] [email protected]