Probe charmonium-nucleon interactions in high energy proton-proton collisions

Abstract

We investigate charmonium production and the charmonium-nucleon correlation function in pp collisions using the EPOS4+CATS framework. For the first time, the emission source of charmonium-proton pairs is dynamically generated and found to be non-Gaussian. This enables a femtoscopic extraction of the charmonium-proton interaction directly from experimental correlation functions. Both ground and excited charmonium states are included. We find that feed-down from excited charmonium states can induce sizable modifications to the observed prompt $J/\psi$-proton correlation function, even when the correlation deviates from unity by less than one, reflecting the stronger interactions of the excited states.

9 pages, 7 figures