On Electron-Positron Annihilation into Nucleon-Antinucleon Pairs

Abstract

We discuss the puzzling experimental results on baryon-antibaryon production in e+e- annihilation close to the threshold, in particular the fact that sigma(e+e- --> nbar n) >~ sigma(e+e- --> pbar p). We discuss an interpretation in terms of a two-step process, via an intermediate coherent isovector state serving as an intermediary between e+e- and the baryon-antibaryon system. We provide evidence that the isovector channel dominates both e+e- --> pions and from Nbar N annihilation at rest, and show that the observed ratio of sigma(e+e- --> nbar n)/sigma(e+e- --> pbarp p) can be understood quantitatively in this picture.

13 pages, 4 figures

Cited by in corpus (9)

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• Study of e${}^{+}$e${}^{-}$ $\to \text{p}\overline{\text{p}}{\pi }^0$ in the Vicinity of the $\psi \text{(3770)}$
• Electron-Positron Annihilation into Hadron-Antihadron Pairs
• QCD and e+e- --> Baryon + anti-Baryon
• Timelike and spacelike hadron form factors, Fock state components and light-front dynamics