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arXiv · 2501.18586

Towards more accurate $B_{(s)}\rightarrow\pi(K)$ and $D_{(s)}\rightarrow\pi(K)$ form factors

Logan Roberts·Chris Bouchard·Olmo Francesconi·Will Parrott
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Abstract

We present progress on the calculation of scalar, vector, and tensor form factors for the following meson decays: $B\rightarrow\pi$, $B_s\rightarrow K$, $D\rightarrow\pi$ and $D_s\rightarrow K$. This calculation uses the MILC HISQ gluon field ensembles with HISQ valence quarks. We generate ensembles of correlator data with varying lattice spacings, some as small as 0.044 fm. Some ensembles have a strange-to-light quark mass ratio of 5:1 and others use the physical light quark mass. The fully-relativistic, heavy-HISQ approach is used for the heavy quark, with simulation masses ranging from the charm to near the bottom. This heavy-HISQ approach provides nearly full coverage of the kinematic range.

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Logan Roberts, Chris Bouchard, Olmo Francesconi, Will Parrott. 2025-01-30. Towards more accurate $B_{(s)}\rightarrow\pi(K)$ and $D_{(s)}\rightarrow\pi(K)$ form factors. https://doi.org/10.22323/1.466.0262

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