Electroweak corrections toBs,d→ℓ+ℓ−

Abstract

We calculate the full two-loop electroweak matching corrections to the operator governing the decay Bq → + − in the Standard Model. Their inclusion removes an electroweak scheme and scale uncertainty of about ±7% of the branching ratio. Using different renormalization schemes of the involved electroweak parameters, we estimate residual perturbative electroweak and QED uncertainties to be less than ±1% at the level of the branching ratio.

Bs,d→ℓ+ℓ−Bobeth1, Gorbahn2, Hermann3 et al. 2014Phys. Rev. Lett.Self Cite473403602View full textAdd to dashboardCite

“…This quantity is used to evaluate the W -boson pole mass according to the fit formula in Eqs. (6) and (9) of Ref. [12], which gives M W = 80.358 (8) GeV, consistently with the direct measurement M W = 80.385 (15) GeV [13].…”

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