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Lattice Calculations of Decay Constants

C. Bernard
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Abstract

Lattice attempts to compute the leptonic decay constants of heavy-light pseudoscalar mesons are described. I give a short historical overview of such attempts and then discuss some current calculations. I focus on three of the most important sources of systematic error: the extrapolation to the continuum, the chiral extrapolation in light quark mass, and the effects of quenching. I briefly discuss the ``bag parameters'' $B_B$ and $B_{B_s}$, and then conclude with my expectations of the precision in decay constants and bag parameters that will be possible in the next few years.

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C. Bernard. 1997-09-25. Lattice Calculations of Decay Constants. https://arxiv.org/abs/hep-ph/9709460

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