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arXiv · 2408.13776

Study of the semileptonic decays $Υ(1S)\to B_{(c)}\ell\barν_\ell$

Chien-Thang Tran·Mikhail A. Ivanov·Pietro Santorelli·Hai-Cat Tran
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Abstract

We study the exclusive semileptonic decays $Υ(1S)\to B_{(c)}\ell\barν_\ell$, where $\ell = e,μ,τ$. The relevant hadronic form factors are calculated using the Covariant Confined Quark Model developed previously by our group. We predict the branching fractions $\mathcal{B}(Υ(1S)\to B_{(c)}\ell\barν_\ell)$ to be of the order of $10^{-13}$ and $10^{-10}$ for the case of $B$ and $B_c$, respectively. Our predictions agree well with other theoretical calculations. We also consider the effects of possible New Physics in the case of $Υ(1S)\to B_cτ\barν_τ$. We show that the branching fraction of this decay can be enhanced by an order of magnitude using constraints from the $B\to D^{(*)}\ell\barν_\ell$ and $B_c\to J/ψ\ell \barν_\ell$ experimental data.

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Chien-Thang Tran, Mikhail A. Ivanov, Pietro Santorelli, Hai-Cat Tran. 2024-11-05. Study of the semileptonic decays $Υ(1S)\to B_{(c)}\ell\barν_\ell$. https://arxiv.org/abs/2408.13776

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