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arXiv · 1605.05645

Semileptonic $B_c$ decays from full lattice QCD

Andrew Lytle·Brian Colquhoun·Christine Davies·Jonna Koponen·Craig McNeile
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Abstract

We present first lattice QCD results for semileptonic form factors for the decays $B_c \to η_c l ν$ and $B_c \to J/ψl ν$ over the full $q^2$ range, using both improved non-relativistic QCD (NRQCD) and fully relativistic (HISQ) formalisms. These can be viewed as prototype calculations for pseudoscalar to pseudoscalar and pseudoscalar to vector decays involving a $b \to c$ transition. In particular we can use information from the relativistic computations to fix the NRQCD current normalisations, which can then be used in improved computations of decays such as $B \to D l ν$ and $B \to D^* l ν$.

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Andrew Lytle, Brian Colquhoun, Christine Davies, Jonna Koponen, Craig McNeile. 2016-05-20. Semileptonic $B_c$ decays from full lattice QCD. https://arxiv.org/abs/1605.05645

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