We present the study of the production of double J/ psi mesons using COMPASS data collected with a 190 GeV/c pi- beam scattering off NH3, Al and W targets. Kinematic distributions of the collected double J/ psi events are analysed, and the double J/ psi production cross section is estimated for each of the COMPASS targets.
The NH3 results are compared to predictions from single-and double-parton scattering models as well as the pion intrinsic charm and the tetraquark exotic resonance hypotheses. It is demonstrated that the single parton scattering production mechanism gives the dominant contribution that is sufficient to describe the data.
An upper limit on the double intrinsic charm content of the pion is evaluated. No significant signatures that could be associated with exotic tetraquarks are found in the double J/ psi mass spectrum. (c) 2023 Published by Elsevier B.V.
This is an open access article under the CC BY license (http:// creativecommons .org /licenses /by /4 .0/). Funded by SCOAP3.