The Study Of T~--â†'e~-P~0(PP) Decays In R-Parity Violating Supersymmetry

Lepton flavor violation (LFV) is one research topic of new physics. An observation of the charged-lepton-flavor violation is a clear signature of new physics since the LFV has a negligibly small probability in the Standard Model (SM) even taking into account neutrino oscillations。SinceÏ„has the largest mass in the three generations of charged Leptons and its decays are allowed to have various kinds of final states, so r is more sensitive thanμand e. r becomes a preferred particle for researching LFV.Now, the relevant process ofÏ„lepton LFV decays mainly coverÏ„lepton rediative decays (Ï„-â†'l-γ),Pure lepton decay(Ï„-â†'l+l-l-) and semileptonic decay(Ï„â†'l-M).In the experiment, Belle and Babar Collaboration were looking for these processes, upper limit reaching O(10-8～10-7).The BR(Ï„-â†'l-Ï€0Ï€0) were probed by CLEO collaboration,the upper limit within O(10-6～10-5].B factory is also aÏ„factory, the luminosity has risen up to 901 fb-1 and has collected many experimental datas of r decays, providing experimental evidences for researching LFV.Theoretically, the above-mentioned decays have been studied in many new physics models beyond SM. The involved models include the topcolor Model, SUSY-seesaw Model, Two-Higgs- Doublet (2HDM) Model, R-Parity Violating Supersymmetry(RPV SUSY) Model, Technicolor Model,LHT Model. Among these models, RPV SUSY Model is one of most attractiving new models.This thesis studies theÏ„-â†'l-P0(Ï€0,η,η') decays andÏ„-â†'l-PP (Ï€0Ï€0,Ï€+Ï€-K+K-,K0K0) under the RPV SUSY Model, l=e,μ.In the RPV SUSY Model, these decays can occurr at the tree level through the sneutrino propagater and squark propagater.,and description of procedure for hadronisation of quark bilinears in the final states within the context of Chrial Perturbation Theory and Resonance Chrial Theory. With the current experimental constraints of decays probability ofÏ„-â†'l-P0 decays andÏ„-â†'l-PP decays renewed in 2010 by Belle Collaboration, the coupling nagnitude of |λ'λ| and |λ'*λ'| have reached to 10-4.At the same time, we consider size relationship of decays branching ratio when mf=100GeV, Lie(μ)=10-3. We also study which propagater is more significant in the same decay mode. v propagater is more sensitive than q propagater except decay process t-â†'l-Ï€+Ï€-.Meanwhile, we get the correlation between model parameters and masses of sparticles with the current experimental constraints:mf∈(100～1000) GeV, L1e(μ) to L5e(μ)∈(10-4～10-2)。Our results have certain referential meaning for probing LFV and distinguish models in the experiment.