A detailed theoretical derivation of the cross sections of e+e−→e+e− and e+e−→μ+μ− around the J/ψ resonance is reported. The resonance and interference parts of the cross sections, related to J/ψ resonance parameters, are calculated. Higher-order corrections for vacuum polarization and initial-state radiation are considered. An arbitrary upper limit of radiative correction integration is involved. Full and simplified versions of analytic formulae are given with precision at the level of 0.1% and 0.2%, respectively. Moreover, the results obtained in the paper can be applied to the case of the ψ(3686) resonance.
@article{arxiv.1701.00218,
title = {Analytical Forms for Cross Sections of Di-lepton Production from $e^+e^-$ Collisions around the $J/\psi$ Resonance},
author = {Xing-Yu Zhou and Ya-Di Wang and Li-Gang Xia},
journal= {arXiv preprint arXiv:1701.00218},
year = {2017}
}