The electromagnetic amplitudes in the $J/\psi$ and $\psi(2S)$ decays into spin-1/2 baryon-antibaryon pairs

TL;DR

This paper analyzes the electromagnetic decay amplitudes of $J/ar{J}$ and $ar{ ext{psi}}(2S)$ into spin-1/2 baryon-antibaryon pairs, providing a parametrization based on BESIII data and predicting cross sections for various baryon pairs.

Contribution

It introduces a full parametrization of EM amplitudes for charged baryon pairs in charmonium decays, extending previous neutral state analysis and making new cross section predictions.

Findings

Parametrization of EM amplitudes for charged baryons in charmonium decays.

Predictions for cross sections of specific baryon-antibaryon pairs at $J/ar{J}$ and $ar{ ext{psi}}(2S)$ masses.

Agreement with BESIII data on $e^+e^- o p ar{p}$ cross section.

Abstract

After investigating the decays of a charmonium $\psi = J/\psi, \psi(2S)$ into a spin-1/2 baryon-antibaryon $B \bar{B}$ pair, with the determination of the only parameter that gives the EM amplitude for neutral final states, in this work we focus our attention on the decays into charged baryons, whose EM amplitudes can be expressed in terms of a further parameter. By considering the BESIII data on the $e^+e^- \to p \overline p$ cross section we obtain a full parametrization for the EM amplitudes and make predictions on the cross section of the decays $e^+ e^- \to \Sigma^+ \overline \Sigma{}^-$, $e^+ e^- \to \Sigma^- \overline \Sigma{}^+$ and $e^+ e^- \to \Xi^- \overline \Xi{}^+$ at the $J/\psi$ and $\psi(2S)$ masses.