Diffractive Double-Elastic Production of $η$' and $η_c$ in the $p p \to p X p$ Reaction

Abstract

I discuss double-diffractive (double-elastic) production of the $η'$ and $η_c$ mesons in the $pp \to p X p$ reaction within the formalism of unintegrated gluon distribution functions (UGDF). The contribution of $γ^* γ^* \to η'$ fusion is estimated. The distributions in the Feynman $x_F$ (or rapidity), transferred four-momenta squared between initial and final protons ($t_1$, $t_2$) and azimuthal angle difference between outgoing protons ($Φ$) are calculated and discussed. The results are compared with the WA102 data. Predictions at higher energies are presented.