Double charmonium production at B factories within light cone formalism

Abstract

This paper is devoted to the study of the processes ${e}^{+}{e}^{\ensuremath{-}}\ensuremath{\rightarrow}J/\ensuremath{\Psi}{\ensuremath{\eta}}_{c}$, $J/\ensuremath{\Psi}{\ensuremath{\eta}}_{c}^{\ensuremath{'}}$, ${\ensuremath{\psi}}^{\ensuremath{'}}{\ensuremath{\eta}}_{c}$, ${\ensuremath{\psi}}^{\ensuremath{'}}{\ensuremath{\eta}}_{c}^{\ensuremath{'}}$ within light cone formalism. It is shown that if one disregards the contribution of higher Fock states, the twist-3 distribution amplitudes needed in the calculation can be unambiguously determined from the twist-2 distribution amplitudes and equations of motion. Using models of the twist-2 distribution amplitudes the cross sections of the processes under study are calculated. The results of the calculation are in agreement with Belle and BABAR experiments. It is also shown that relativistic and radiative corrections to the cross sections play a crucial role in the achievement of the agreement between the theory and experiments. A comparison of the results of this paper with the results obtained in other papers is carried out. In particular, it is shown that the results of the papers where relativistic and radiative corrections were calculated within nonrelativistic QCD are overestimated by a factor of $\ensuremath{\sim}1.5$.