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arXiv · 1811.00227

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

Brian Colquhoun·Shoji Hashimoto·Takashi Kaneko
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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.

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Brian Colquhoun, Shoji Hashimoto, Takashi Kaneko. 2018-11-01. Heavy quark scaling of $B\to\pi\ell\nu$ form factors with M\"{o}bius domain wall fermions. https://arxiv.org/abs/1811.00227

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