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arXiv · 2001.10911

Charmonium contribution to $B \rightarrow K\ell^+\ell^-: testing the factorization approximation on the lattice

Katsumasa Nakayama·Tsutomu Ishikawa·Shoji Hashimoto
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Abstract

We report the current status of a study of charmonium contribution to $B \rightarrow K\ell^+\ell^-$ on the lattice. Our lattice calculation tests the factorization approximation for this contribution. In order to control the problem of the artificial divergence, we focus on the low $q^2$ region with a small b-quark mass. We also take into account the renormalization constants of relevant four-quark operators calculated through the temporal moments. Results suggest a violation of the factorization approximation.

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Katsumasa Nakayama, Tsutomu Ishikawa, Shoji Hashimoto. 2020-01-29. Charmonium contribution to $B \rightarrow K\ell^+\ell^-: testing the factorization approximation on the lattice. https://arxiv.org/abs/2001.10911

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