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arXiv · hep-lat/9910020

An Investigation of the Soft Pion Relation in Quenched Lattice QCD

UKQCD Collaboration·K. C. Bowler·C. M. Maynard·L. Lellouch·J. Nieves·D. G. Richards·L. Del Debbio·J. M. Flynn·V. I. Lesk
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Abstract

A lattice determination of the form factor and decay constants for the semileptonic decay of heavy pseudoscalar (PS) mesons at zero recoil is presented from which the soft pion relation is satisfied. Chiral extrapolation of the form factor is performed at constant $q^2$. Pole dominance is used to extrapolate the form factor in heavy quark mass. At the B mass, the form factor at zero recoil lies somewhat below the ratio of decay constants; the relation remains satisfied within error.

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UKQCD Collaboration, K. C. Bowler, C. M. Maynard, L. Lellouch, J. Nieves, D. G. Richards, L. Del Debbio, J. M. Flynn, V. I. Lesk. 1999-10-08. An Investigation of the Soft Pion Relation in Quenched Lattice QCD. https://doi.org/10.1016/s0920-5632(00)91658-x

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