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arXiv · 0802.1563

Determination of B*B pi coupling in unquenched QCD

Hiroshi Ohki·Hideo Matsufuru·Tetsuya Onogi
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Abstract

The $B^* Bπ$ coupling is a fundamental parameter of chiral effective Lagrangian with heavy-light mesons and can constrain the chiral behavior of $f_B$, $B_B$ and the $B\to πl ν$ form factor in the soft pion limit. We compute the $B^* B π$ coupling with the static heavy quark and the $O(a)$-improved Wilson light quark. Simulations are carried out with $n_f=2$ unquenched $12^3\times 24$ lattices at $β=1.80$ and $16^3\times 32$ lattices at $β=1.95$ generated by CP-PACS collaboration. To improve the statistical accuracy, we employ the all-to-all propagator technique and the static quark action with smeared temporal link variables following the quenched study by Negishi {\it et al.}. These methods successfully work also on unquenched lattices, and determine the $B^*Bπ$ coupling with 1--2% statistical accuracy on each lattice spacing.

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Hiroshi Ohki, Hideo Matsufuru, Tetsuya Onogi. 2008-02-12. Determination of B*B pi coupling in unquenched QCD. https://doi.org/10.1103/physrevd.77.094509

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