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arXiv · 1411.1651

Kaon and D meson semileptonic form factors from lattice QCD

Thomas Primer·Doug Toussaint·Aida El-Khadra·Elvira Gámiz·James Simone
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Abstract

We present the status of on-going calculations of the $K\toπlν$ and $D\to K(π) lν$ semileptonic form factors at $q^2=0$. These form factors are important for the determination of the CKM matrix elements $\lvert{V_{us}}\rvert$ and $\lvert{V_{cs(d)}}\rvert$ respectively. This work uses the HISQ action for both valence quarks and sea quarks on MILC $N_f=2+1+1$ configurations. We employ twisted boundary conditions to calculate the form factors at zero momentum transfer directly. The $K\toπ$ results are an update to previously published results with new data at the physical point. The $D\to K(π)$ results are preliminary.

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Thomas Primer, Doug Toussaint, Aida El-Khadra, Elvira Gámiz, James Simone. 2014-11-06. Kaon and D meson semileptonic form factors from lattice QCD. https://arxiv.org/abs/1411.1651

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