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arXiv · 1411.4227

Improved currents for $\bar{B}\to D^{(*)}\ell\barν$ form factors from 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 experimentally determined branching fractions for $\bar{B}\to D^{(*)}\ell\barν$ decays with form factors from the lattice. While successful, the precision of this approach has been limited by heavy-quark discretization effects. An improved version of the Fermilab action, the Oktay-Kronfeld action, can be used to reduce heavy-quark discretization effects in calculations performed at the physical bottom and charm quark masses. Treating charm and bottom quarks as massive, we are carrying out improvement of the flavor-changing currents through third order in the momentum (HQET) expansion.

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Jon A. Bailey, Yong-Chull Jang, Weonjong Lee, Jaehoon Leem. 2014-11-16. Improved currents for $\bar{B}\to D^{(*)}\ell\barν$ form factors from Oktay-Kronfeld heavy quarks. https://arxiv.org/abs/1411.4227

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