Baryonic rare decays of Λb→Λl+l- -: art. no. 074001

We present a systematic analysis for the rare baryonic exclusive decays of Lambda (b)--> Lambdal(+)l(-) (l=e,mu,tau). We study the differential decay rates and the dilepton forward-backward, lepton polarization, and various CP asymmetries with a new simple set of form factors inspired by the heavy quark effective theory. We show that most of the observables a-re insensitive to the nonperturbative QCD effects. To illustrate the effect of new physics, we discuss our results in an explicit supersymmetric extension of the standard model, which contains new CP violating phases and therefore induces sizable CP violating asymmetries.