Theoretical progress in describing the B-meson lifetimes

TL;DR

This paper reviews the current theoretical estimates of B-meson lifetimes and mixing parameters, updating lattice QCD results for relevant matrix elements and including NLO corrections, providing refined predictions for lifetime ratios and width differences.

Contribution

It presents new lattice QCD results for (delta B=0)-operator matrix elements and incorporates NLO corrections, advancing the theoretical understanding of B-meson properties.

Findings

Updated lattice results for matrix elements

Predicted B-meson lifetime ratios and width differences

Inclusion of NLO QCD corrections

Abstract

The present status of the theoretical estimates of the difference between the widths of the neutral Bs-mesons and of the B-meson lifetime ratios is reviewed. In particular, the lattice results for the matrix elements of the relevant (delta B=2)-operators are updated and the first lattice QCD results for the matrix elements of (delta B=0)-operators are presented. In both cases, the NLO perturbative QCD corrections in the coefficient functions have been included. The theoretically updated results are: (delta Gamma/Gamma)_{Bs} = (7 +/- 4) %, tau(B+)/tau(Bd) = 1.07(3) and tau(Bs)/tau(Bd) = 1.00(2).