Theory of time-like baryon form factors near thresholds

Abstract

A new mechanism of baryon-antibaryon production via nonperturbative double pair creation in intermediate mesons is proposed and the theory contains no fitting parameters. It is shown, that near-threshold resonances are responsible for enhancements in electroproduction cross sections: $\psi (4S)$ for ${\Lambda }_c^{+}{\Lambda }_c^{-},{\rm Y}(6S)$ for ${\Lambda }_b{\bar{\Lambda }}_b$. An admixture of intermediate $D$- wave resonances produces angular dependence in differential cross section and can explain unusual behavior of the ratio $G_E/G_M$ for the proton.

Comments: 5 pages,4 figures