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arXiv · 2101.01477

One-loop corrections to the processes $e^+e^- \to \gamma, Z \to J/\psi~\eta_c$ and $e^+e^- \to Z \to J/\psi~J/\psi$

A. V. Berezhnoy·I. N. Belov·S. V. Poslavsky·A. K. Likhoded
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Abstract

The cross section values of $J/\psi\ \eta_c$ and $J/\psi\ J/\psi$ production in $e^+e^-$ annihilation are estimated within one-loop approximation near $Z$ pole, as well as at higher energies. Both intermediate bosons, $\gamma$ and $Z$, are taken into account. It is shown that at $Z$ mass the NLO contribution increases the cross-section values by 3.5 times.

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A. V. Berezhnoy, I. N. Belov, S. V. Poslavsky, A. K. Likhoded. 2021-01-05. One-loop corrections to the processes $e^+e^- \to \gamma, Z \to J/\psi~\eta_c$ and $e^+e^- \to Z \to J/\psi~J/\psi$. https://doi.org/10.1103/physrevd.104.034029

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