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arXiv · 2110.12045

Towards two- and three-loop QCD corrections to the width difference in $B_s-\bar{B}_s$ mixing

Vladyslav Shtabovenko
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Abstract

In this work we address the issue of large perturbative uncertainties in the theory prediction for $ΔΓ_s$, the width difference in the $B^0_s - \bar{B}^0_s$ mixing process. To this aim we complete important steps towards the full analytic result for the previously unknown Wilson coefficients from the matching between $|ΔB|=1$ and $|ΔB|=2$ effective Hamiltonians at next-to-next-leading order (NNLO) in the strong coupling constant. We provide a thorough discussion of technical and conceptual difficulties behind this computation and give an outlook regarding the availability of the new NNLO theory prediction for $ΔΓ_s$.

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Vladyslav Shtabovenko. 2021-10-22. Towards two- and three-loop QCD corrections to the width difference in $B_s-\bar{B}_s$ mixing. https://arxiv.org/abs/2110.12045

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