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arXiv · 2306.16804

Total cross section of the process $e^+ + e^- \to Σ^0 + \barΣ^0$ in the vicinity of charmonium $ψ(3770)$ including the $D$-meson loop and three gluon contributions

Abstract

For the study of the structure of baryons it is necessary to investigate the production of a baryon pair in $e^+e^-$ annihilation. The baryon-antibaryon pair production at the electron-positron linear collider makes it possible to investigate in detail the basic structure of the Standard Model. The creation of baryon-antibaryon pairs in electron-positron annihilation provides an increasingly powerful tool at higher c.m. energies. We present phenomenological results for $Σ^0 \bar Σ^0$ production in $e^+e^-$ interaction at the BESIII and BABAR Colliders. In the present work, we investigate a hyperon pair produced in the reaction $e^+e^- \to Σ^0 \barΣ^0$. We calculate the total cross section of the process $e^+e^- \to Σ^0 \bar Σ^0$ taking into account the contributions of the $D$-meson loop and three gluon loops as well as the interference of all diagrams to the Born approximation. For these contributions large relative phases are generated with respect to the pure electromagnetic mechanism. For the large momentum transferred region we obtain as a byproduct a fit of the electromagnetic form factor of the $Σ$ hyperon.

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Azad I. Ahmadov. 2024-05-28. Total cross section of the process $e^+ + e^- \to Σ^0 + \barΣ^0$ in the vicinity of charmonium $ψ(3770)$ including the $D$-meson loop and three gluon contributions. https://arxiv.org/abs/2306.16804

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