$J/\psi + c + \bar{c}$ Photoproduction in $e^+ e^-$ Scattering

Abstract

We investigate the $J/\psi$ + c + $\bar{c}$ photoproduction in $e^+ e^-$ collision at the LEP II energy. The physical motivations for this study are: 1) such next-to-leading order(NLO) process was not considered in previous investigations of $J/\psi$ photoproduction in $e^+ e^-$ interaction, and it is worthwhile to do so in order to make sound predictions for experimental comparison; 2) from recent Belle experiment results, the process with same final states at the $B$ factory has a theoretically yet unexplainable large fraction; hence it is interesting to see what may happen at other colliders; 3) the existing LEP data are marginal in observing such process, and at the planed Linear Colliders(LCs) this process can be measured with high accuracy; 4) it is necessary to take this process into consideration in the aim of elucidating the quarkonium production mechanism, especially in testing the universality of NRQCD nonperturbative matrix elements via $J/\psi$ photoproduction in electron-position collisions.