New physics contributions to moments of inclusive b → c semileptonic decays

Abstract

Abstract Inclusive semileptonic B → X c ℓ ν ¯ ℓ $$ {X}_c\ell {\overline{\nu}}_{\ell } $$ decays, where ℓ = μ, e, are by now standard candles in the determination of the CKM element |V cb |. These determinations rely on the heavy-quark expansion and use moments of decay spectra to extract the non-perturbative parameters directly from data under the standard model assumption. At the same time, new physics could influence the moments of the inclusive decay. In this paper, we compute power-corrections and next-to-leading order corrections in the strong coupling constant using the full basis of dimension-six new physics operators for the inclusive B → X c ℓ ν ¯ $$ {X}_c\ell \overline{\nu} $$ decay. We provide predictions for lepton energy, hadronic and leptonic invariant mass moments, and perform a phenomenological study to show the possible impact of new physics. Our results could be used to perform a global fit including new physics contributions.

Keywords

• Semi-Leptonic Decays
• Bottom Quarks
• Other Weak Scale BSM Models