Heavy quark scaling of $B\to\pi\ell\nu$ form factors with M\"{o}bius domain wall fermions

TL;DR

This paper presents a lattice QCD calculation of $B o \pi u \\ell$ form factors using M"obius domain wall fermions across multiple lattice spacings and pion masses, extrapolating to the physical bottom quark mass.

Contribution

It introduces a new calculation of $B o \\pi$ form factors with M"obius domain wall fermions on fine lattices, covering a range of heavy quark masses and pion masses.

Findings

Form factors depend on pion mass, heavy quark mass, and lattice spacing.

Extrapolation techniques used to reach physical bottom quark mass.

Results show consistency with theoretical expectations.

Abstract

We report on the progress of our calculation of form factors for the exclusive semileptonic decay of $B$ mesons to pions on $2+1$ flavour lattices with spacings from $0.080~\mathrm{fm}$ down to $0.044~\mathrm{fm}$. Using the M\"{o}bius domain wall fermion action for all quarks, we simulate pions with masses down to $230~\mathrm{MeV}$ and extrapolate to the physical bottom quark mass by utilizing a range of heavy quark masses up to $2.44$ times the mass of the charm quark. We discuss the dependence on the pion mass, heavy quark mass and lattice spacing in our form factors results.