One-nucleon intermediate-state contribution to the pion-coupled four-quark condensate in the $N$--$J/\psi$ interaction
The density dependence of four-quark condensates is a major source of uncertainty in operator product expansion analyses of hadrons in nuclear matter. Their determination is particularly relevant to the $N$--$J/\psi$ interaction, whose long-range attraction appears to be well described by two-pion exchange in lattice Q...