Inclusive semileptonic Λb decays in the Standard Model and beyond

Abstract

Inclusive semileptonic decays of beauty baryons are studied using the heavy quark expansion to O(1/mb3), at leading order in αs. The case of a polarized decaying baryon is examined, with reference to Λb. An extension of the Standard Model effective Hamiltonian inducing b → Uℓ ν¯ ℓ transitions (U = u, c and ℓ = e, μ, τ) is considered, which comprises the full set of D=6 semileptonic operators with left-handed neutrinos. The effects of the new operators in several observables are described.