Phenomenology of V_ub from Ratios of Inclusive B Decay Rates

TL;DR

This paper investigates methods to determine the CKM matrix element V_ub from ratios of inclusive B meson decay rates, analyzing theoretical uncertainties from perturbative and nonperturbative effects.

Contribution

It introduces two ratios of inclusive B decay rates that can be used to extract V_ub with about 10% theoretical uncertainty, considering both perturbative and nonperturbative contributions.

Findings

Ratios R_1 and R_2 can be computed with ~10% uncertainty.

Theoretical analysis of perturbative and nonperturbative effects.

Feasibility of extracting V_ub from inclusive decay ratios.

Abstract

We explore the theoretical feasibility of extracting V_ub from two ratios built from B meson inclusive partial decays, R_1 = Gamma(b-> u cbar s)/3Gamma(b -> c l nu), and R_2 = [Gamma(b -> c X) - Gamma(b -> cbar X)]/Gamma(b -> c ubar d). We discuss contributions to these quantities from perturbative and nonperturbative physics, and show that they can be computed with overall uncertainties at the level of 10%.