Momentum Transfer Dependence of the Differential Cross Section for $J/\psi$ Production

Abstract

We discuss the $t$ dependence of $J/\psi$ production in the region of $0<-t<M_{\psi }^2$. The forward slope of the elastic differential cross section is calculated assuming a dipole-type dependence for the gluon ladder-proton form factor. The $t$ dependence of $d\sigma /dt$ is obtained using DGLAP evolution both for the elastic channel at low $-t$ and for the inelastic channel at large values of $-t$, up to $-t\simeq M_{\psi }^2$. Results are presented and compared with the relevant experimental data.

Comments: Revised version