Possible contributions toe+e−→J/ψ+ηcdue to intermediate meson rescatterings

Abstract

Inspired by the obvious discrepancies between experiment and nonrelativistic QCD (NRQCD) studies of e(+)e(-) -> J/psi + eta(c) at root s similar or equal to 10.6 GeV , we investigate contributions from intermediate meson loops as long-range interaction transitions to this process. The intermediate meson loops include D (D) over bar((D) over bar*), D (D) over bar* (D or (D) over bar*, D*(D) over bar*(D) and corresponding D-s intermediate mesons. With the constraints from experimental data on the vertex couplings, we find that the intermediate meson loops account for 2.7 similar to 6.7 fb of the cross sections within a reasonable range of cutoff energies of the factor parameter. We also investigate contributions from the absorptive part and find that it accounts for approximately 0.58 similar to 1.38 fb. These results imply that contributions from long-range interaction transitions may still play a role in such an energy region.