On Electron-Positron Annihilation into Nucleon-Antinucleon Pairs
High Energy Physics - Phenomenology
2009-09-11 v1
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.
Keywords
Cite
@article{arxiv.hep-ph/0108259,
title = {On Electron-Positron Annihilation into Nucleon-Antinucleon Pairs},
author = {John Ellis and Marek Karliner},
journal= {arXiv preprint arXiv:hep-ph/0108259},
year = {2009}
}
Comments
13 pages, 4 figures