Speaker
Description
Exclusive photoproduction of heavy $J/\Psi$ meson is performed within the handbag
approach where amplitudes factorize into hard subprocesses and generalized parton
distributions (GPDs). The general parton distributions (GPDs) for gluons $H_g$, are
constructed using double distribution representation. The calculated cross section for
few sets of $H_g$, GPDs describe fine $J/\Psi$ production experimental data from HERA to LHC energies \cite{1}.
Within this approach we estimate $J/\Psi$ spin asymmetries determined by $E_g$ and $H_g$ GPDs. Some
predictions for future electron-ion colliders in USA and China are done.
We extend our model calculations to exclusive $J/\Psi$ production in
proton–proton collisions. The survival factors and equivalent
photon approximation are applied to predict the exclusive
$J/\Psi$ production in pp collisions. Obtained results are in a good
agreement with the experimental data at LHCb \cite{2}. We predict the exclusive
$J/\Psi$ production cross section at RHIC and NICA energies.
Our GPD approach predictions can be employed to estimate the
exclusive $J/\Psi$ production abservables in future lepton–proton and proton–proton experiments
to get essential information on gluon GPDs.
- S. V. Goloskokov, Ya-Ping Xie and Xurong Chen, Phys.Rev {\bfseries D110}, 076029 (2024),
arXiv:2408.05800 [hep-ph]. - Ya-Ping Xie, S. V. Goloskokov, Eur. Phys. J. C {\bfseries 85},680 (2025), arXiv:2502.17743 [hep-ph].
