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arXiv · 2403.03959

$B$-meson semileptonic decays from highly improved staggered quarks

Andrew Lytle·Carleton DeTar·Aida El-Khadra·Elvira Gámiz·Steven Gottlieb·William Jay·Andreas Kronfeld·Jack Laiho·James Simone·Alejandro Vaquero
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Abstract

We present an update for results on $B$-meson semileptonic decays using the highly improved staggered quark (HISQ) action for both valence and 2+1+1 sea quarks. The use of the highly improved action, combined with the MILC collaboration's gauge ensembles with lattice spacings down to $\sim$0.03 fm, allows the $b$ quark to be treated with the same discretization as the lighter quarks. The talk will focus on updated results for $B_{(s)} \to D_{(s)}$, $B_{(s)} \to K$ scalar and vector form factors.

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Andrew Lytle, Carleton DeTar, Aida El-Khadra, Elvira Gámiz, Steven Gottlieb, William Jay, Andreas Kronfeld, Jack Laiho, James Simone, Alejandro Vaquero. 2024-02-18. $B$-meson semileptonic decays from highly improved staggered quarks. https://arxiv.org/abs/2403.03959

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