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arXiv · 1311.1143

The form factors for B -> pi l nu semileptonic decay from 2+1 flavors of domain-wall fermions

Taichi Kawanai·Ruth S. Van de Water·Oliver Witzel
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Abstract

We present a calculation of the B -> pi l nu form factors with domain-wall light quarks and relativistic b-quarks on the lattice. We work with the 2+1 flavor domain-wall fermion and Iwasaki gauge-field ensembles generated by the RBC and UKQCD Collaborations. The chiral-continuum extrapolation is performed using SU(2) hard-pion chiral perturbation theory. To extrapolate the lattice form factors to the full kinematic range, we use the model independent z-parameterization and impose the kinematic constraint f_+(0) = f_0(0) at zero momentum transfer.

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Taichi Kawanai, Ruth S. Van de Water, Oliver Witzel. 2013-11-05. The form factors for B -> pi l nu semileptonic decay from 2+1 flavors of domain-wall fermions. https://arxiv.org/abs/1311.1143

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