B Decays in the Upsilon Expansion

TL;DR

This paper introduces a novel approach to predicting B decay rates by rewriting calculations in terms of the Upsilon meson mass, which improves series convergence and reduces theoretical uncertainties.

Contribution

The paper presents a modified perturbation expansion using the Upsilon mass, enhancing prediction accuracy for B decays and eliminating dominant quark mass uncertainties.

Findings

Improved convergence of decay rate series.

Reduced theoretical errors from quark mass uncertainties.

Enhanced predictions for CKM elements and decay spectra.

Abstract

Theoretical predictions for B decay rates are rewritten in terms of the Upsilon meson mass instead of the b quark mass, using a modified perturbation expansion. The theoretical consistency is shown both at low and high orders. This method improves the behavior of the perturbation series for inclusive and exclusive decay rates, and the largest theoretical error in the predictions coming from the uncertainty in the quark mass is eliminated. Applications to the determination of CKM matrix elements, moments of inclusive decay distributions, and the B -> X_s \gamma photon spectrum are discussed.