Study the Origin of Proton Mass with Near Threshold J/$\psi$ Production*

Nucleons compose almost all visible mass in our universe. Yet, our understanding of nucleon mass, especially the QCD trace anomaly's role, is still limited. Production of $J/\psi$ near its threshold provides a unique probe to the nucleon's gluonic structure, enabling access to the dynamic origin of the nucleon mass. The SoLID-$J/\psi$ experiment (JLab E12-12-006) will measure the near-threshold differential $J/\psi$ production cross-section with high statistical precision and obtain crucial input to determine the trace anomaly contribution to the proton mass. I will discuss the projected impact on the trace anomaly term from the SoLID-$J/\psi$ experiment and the complementarity of SoLID-$J/\psi$ with the future EIC experiments.