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arXiv · 1511.04000

$D$-meson semileptonic form factors at zero momentum transfer in (2+1+1)-flavor lattice QCD

Thomas Primer·Claude Bernard·Carleton DeTar·Aide El-Khadra·Elvira Gámiz·Javad Komijani·Andreas Kronfeld·James Simone·Doug Toussaint·Ruth S. Van de Water
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Abstract

We present a calculation of the $D\to K \ell ν$ and $D\toπ\ell ν$ semileptonic form factors at $q^2=0$, which enable determinations of the CKM matrix elements $\lvert{V_{cs}}\rvert$ and $\lvert{V_{cd}}\rvert$, respectively. We use gauge-field configurations generated by the MILC collaboration with four flavors of highly-improved staggered (HISQ) quarks, analyzing several ensembles including those with physical pion masses and approximate lattice spacings ranging from 0.12~fm to 0.042~fm. We also use the HISQ action for the valence quarks. We employ twisted boundary conditions to calculate the form factors at zero momentum transfer directly. We use heavy-light-meson chiral perturbation theory modified for energetic pions and kaons, and supplemented by terms to describe the lattice-spacing dependence, to obtain preliminary results at the physical point and in the continuum limit.

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Thomas Primer, Claude Bernard, Carleton DeTar, Aide El-Khadra, Elvira Gámiz, Javad Komijani, Andreas Kronfeld, James Simone, Doug Toussaint, Ruth S. Van de Water. 2015-11-12. $D$-meson semileptonic form factors at zero momentum transfer in (2+1+1)-flavor lattice QCD. https://arxiv.org/abs/1511.04000

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