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arXiv · 1710.08161

Direct, Resonant Production of States with Positive Charge Conjugation in Electron-Positron Annihilation

Henryk Czyż·Johann H. Kühn·Szymon Tracz
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Abstract

Recent theory results on direct production of resonances with positive charge conjugation in electron-positron annihilation are reviewed. The strong model dependence is emphasized, with predictions varying between 0.03 eV and 0.43 eV for the charmonium state with $J^{PC} = 1^{++}$ and between 0.16 eV and 4.25 eV for the state with $J^{PC} = 2^{++}$. For the state with $J^{PC} = 0^{++}$ the cross section is of $\cal{O}$ $(m^2_e/M^2_{\chi})$ and thus negligeable for all practical purpose. The importance of the relative phase of the production amplitude is emphasized.

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Henryk Czyż, Johann H. Kühn, Szymon Tracz. 2017-10-23. Direct, Resonant Production of States with Positive Charge Conjugation in Electron-Positron Annihilation. https://arxiv.org/abs/1710.08161

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