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Towards a lattice determination of the $B^\ast B π$ coupling

G. M. de Divitiis·L. Del Debbio·M. Di Pierro·J. M. Flynn·C. Michael·J. Peisa·UKQCD Collaboration
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Abstract

The coupling $g_{B^\ast B π}$ is related to the form factor at zero momentum of the axial current between $B^\ast$- and $B$-states. This form factor is evaluated on the lattice using static heavy quarks and light quark propagators determined by a stochastic inversion of the fermionic bilinear. The $\gBBP$ coupling is related to the coupling $g$ between heavy mesons and low-momentum pions in the effective heavy meson chiral lagrangian. The coupling of the effective theory can therefore be computed by numerical simulations. We find the value $g = 0.42(4)(8)$. Besides its theoretical interest, the phenomenological implications of such a determination are discussed.

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G. M. de Divitiis, L. Del Debbio, M. Di Pierro, J. M. Flynn, C. Michael, J. Peisa, UKQCD Collaboration. 1998-07-20. Towards a lattice determination of the $B^\ast B π$ coupling. https://arxiv.org/abs/hep-lat/9807032

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