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arXiv · 1711.01777

Improvement of heavy-heavy current for calculation of $\bar{B}\to D^{(*)}\ell\barν$ form factors using Oktay-Kronfeld heavy quarks

Jon A. Bailey·Yong-Chull Jang·Weonjong Lee·Jaehoon Leem
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Abstract

The CKM matrix element $|V_{cb}|$ can be extracted by combining data from experiments with lattice QCD results for the semileptonic form factors for the $\bar{B}\to D^{(*)} \ell \barν$ decays. The Oktay-Kronfeld (OK) action was designed to reduce heavy-quark discretization errors to below $1\%$, or through $\mathcal{O}(λ^3)$ in HQET power counting. Here we describe recent progress on bottom-to-charm currents improved to the same order in HQET as the OK action, and correct formerly reported results of our matching calculations, in which the operator basis was incomplete.

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Jon A. Bailey, Yong-Chull Jang, Weonjong Lee, Jaehoon Leem. 2017-11-09. Improvement of heavy-heavy current for calculation of $\bar{B}\to D^{(*)}\ell\barν$ form factors using Oktay-Kronfeld heavy quarks. https://doi.org/10.1051/epjconf%2F201817514010

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