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arXiv · 2406.16084

Update on technical aspects of $B$ meson mixing at NNLO

Pascal Reeck
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Abstract

This report summarises important technical challenges and their solutions in the calculation of the next-to-next-to-leading order QCD corrections to the width difference $\Delta\Gamma_s$ in the $B_s-\overline{B}_s$ system. We focus on the treatment of spinor structures with products of up to 22 $\gamma$ matrices by means of projection and tensor integrals. Moreover, we present an approach for the semi-numeric computation of master integrals.

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Pascal Reeck. 2024-06-23. Update on technical aspects of $B$ meson mixing at NNLO. https://arxiv.org/abs/2406.16084

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