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arXiv · 1011.2423

Semileptonic decays of K and D mesons in 2+1 flavor QCD

Jon A. Bailey·A. Bazavov·C. Bernard·C. M. Bouchard·C. DeTar·A. X. El-Khadra·E. D. Freeland·E. Gamiz·Steven Gottlieb·U. M. Heller·J. E. Hetrick·A. S. Kronfeld·J. Laiho·L. Levkova·P. B. Mackenzie·M. B. Oktay·J. N. Simone·R. Sugar·D. Toussaint·R. S. Van de Water
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Abstract

The experimentally measured rates of the semileptonic decays K -> pi l nu and D -> K(pi) l nu can be combined with lattice calculations of the associated form factors to precisely extract the CKM matrix elements |V_{us}| and |V_{cs(d)}|. We report on the status of form factor calculations with Fermilab charm quarks and staggered light quarks on the 2+1 flavor asqtad staggered MILC ensembles. Analysis of data for the D -> pi l nu form factor provides a nontrivial test of our methods via comparison with CLEO data. We discuss the use of HISQ valence quarks to calculate the K -> pi l nu form factor f_+^{K pi}(0) and describe tests of our method.

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Jon A. Bailey, A. Bazavov, C. Bernard, C. M. Bouchard, C. DeTar, A. X. El-Khadra, E. D. Freeland, E. Gamiz, Steven Gottlieb, U. M. Heller, J. E. Hetrick, A. S. Kronfeld, J. Laiho, L. Levkova, P. B. Mackenzie, M. B. Oktay, J. N. Simone, R. Sugar, D. Toussaint, R. S. Van de Water. 2010-11-10. Semileptonic decays of K and D mesons in 2+1 flavor QCD. https://arxiv.org/abs/1011.2423

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