Comparison of lattice QCD results for inclusive semi-leptonic decays of $B$ mesons with the OPE

TL;DR

This paper compares lattice QCD calculations of inclusive semi-leptonic B meson decays with OPE predictions, highlighting differences and strategies to reduce uncertainties in theoretical predictions.

Contribution

It introduces a lattice QCD approach for inclusive decay rates and systematically compares it with OPE-based predictions, including power corrections.

Findings

Lattice results differ from OPE predictions for unphysical bottom quark masses.

Strategies to reduce systematic uncertainties are discussed.

Comparison provides insights into non-perturbative effects in B decays.

Abstract

A recently proposed approach to compute the inclusive semi-leptonic decay rate on the lattice allows for the calculation of various quantities (differential distributions and moments) in different subchannels. We systematically compare the lattice QCD results for an unphysically light bottom quark with OPE-based predictions, including leading order perturbative and $\mathcal{O}\left(1/m^3 \right)$ power corrections, and explore possible strategies to decrease the systematic uncertainty.