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arXiv · 1710.07334

$D \rightarrow Kl{\nu}$ semileptonic decay using lattice QCD with HISQ at physical pion masses

Bipasha Chakraborty·Christine Davies·Jonna Koponen·G Peter Lepage
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Abstract

The quark flavor sector of the Standard Model is a fertile ground to look for new physics effects through a unitarity test of the Cabbibo-Kobayashi-Maskawa (CKM) matrix. We present a lattice QCD calculation of the scalar and the vector form factors (over a large $q^2$ region including $q^2 = 0$) associated with the $D \rightarrow Kl{\nu}$ semi-leptonic decay. This calculation will then allow us to determine the central CKM matrix element, $V_{cs}$ in the Standard Model, by comparing the lattice QCD results for the form factors and the experimental decay rate. This form factor calculation has been performed on the $N_f =2+1+1$ MILC HISQ ensembles with the physical light quark masses.

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Bipasha Chakraborty, Christine Davies, Jonna Koponen, G Peter Lepage. 2017-10-19. $D \rightarrow Kl{\nu}$ semileptonic decay using lattice QCD with HISQ at physical pion masses. https://doi.org/10.1051/epjconf%2F201817513027

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