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arXiv · 1710.09442

Semileptonic $B$-meson decays to light pseudoscalar mesons on the HISQ ensembles

Zechariah Gelzer·C. Bernard·C. DeTar·A. X. El-Khadra·E. Gámiz·Steven Gottlieb·Andreas S. Kronfeld·Yuzhi Liu·Y. Meurice·J. N. Simone·D. Toussaint·R. S. Van de Water·R. Zhou
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Abstract

We report the status of an ongoing lattice-QCD calculation of form factors for exclusive semileptonic decays of $B$ mesons with both charged currents ($B\to\pi\ell\nu$, $B_s\to K\ell\nu$) and neutral currents ($B\to\pi\ell^+\ell^-$, $B\to K\ell^+\ell^-$). The results are important for constraining or revealing physics beyond the Standard Model. This work uses MILC's (2+1+1)-flavor ensembles with the HISQ action for the sea and light valence quarks and the clover action in the Fermilab interpretation for the $b$ quark. Simulations are carried out at three lattice spacings down to $0.088$ fm, with both physical and unphysical sea-quark masses. We present preliminary results for correlation-function fits.

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Zechariah Gelzer, C. Bernard, C. DeTar, A. X. El-Khadra, E. Gámiz, Steven Gottlieb, Andreas S. Kronfeld, Yuzhi Liu, Y. Meurice, J. N. Simone, D. Toussaint, R. S. Van de Water, R. Zhou. 2017-10-25. Semileptonic $B$-meson decays to light pseudoscalar mesons on the HISQ ensembles. https://doi.org/10.1051/epjconf/201817513024

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