Next-to-leading-order relativistic and QCD corrections to prompt pair photoproduction at future colliders*

Abstract

Within the framework of nonrelativistic-QCD factorization, we calculate both the 
next-to-leading-order relativistic and QCD corrections to prompt $J/\psi$ pair production, with 
feeddown from $\psi(2S)$ mesons, via photon-photon collisions at future $e^+e^-$ colliders including 
the Future Circular Lepton Collider (FCC-ee), the Circular Electron Positron Collider (CEPC), and 
the Compact Linear Collider (CLIC). We present total cross sections and distributions in single 
$J/\psi$ transverse momentum and rapidity, and in $J/\psi$ pair invariant mass. The relativistic and 
QCD corrections both turn out to be large and negative. Yet, the production rates are large enough 
for useful experimental studies. Content from this work may be used under the terms of the Creative Commons Attribution 3.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI. Article funded by SCOAP3 and published under licence by Chinese Physical Society and the Institute of High Energy Physics of the Chinese Academy of Science and the Institute of Modern Physics of the Chinese Academy of Sciences and IOP Publishing Ltd.