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arXiv · 1912.11770

$B\!\to\!D^{(*)}\ell\nu$ form factors from lattice QCD with relativistic heavy quarks

T. Kaneko·Y. Aoki·G. Bailas·B. Colquhoun·H. Fukaya·S. Hashimoto·J. Koponen
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Abstract

We report on our calculation of the B \to D^(*) \ell \nu form factors in 2+1 flavor lattice QCD. The M\"obius domain-wall action is employed for light, strange, charm and bottom quarks. At lattice cutoffs 1/a \sim 2.4, 3.6 and 4.5 GeV, we simulate bottom quark masses up to 0.7/a to control discretization errors. The pion mass is as low as 230 MeV. We extrapolate the form factors to the continuum limit and physical quark masses, and make a comparison with recent phenomenological analyses.

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T. Kaneko, Y. Aoki, G. Bailas, B. Colquhoun, H. Fukaya, S. Hashimoto, J. Koponen. 2019-12-26. $B\!\to\!D^{(*)}\ell\nu$ form factors from lattice QCD with relativistic heavy quarks. https://arxiv.org/abs/1912.11770

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