QCD analysis of near-threshold quarkonium leptoproduction at large photon virtualities

We propose a novel approach to compute the cross section of near-threshold J /ψ and ϒ production in electron-proton scattering at large photon virtualities Q² based on an operator product expansion. We show that the process can be used to extract the gluon part of the D-term gravitational form factor of the proton. At the subleading level, it is also sensitive to the trace anomaly effect of QCD.