A QCD Calculation of the Interaction of Quarkonium with Nuclei

Abstract

The interaction of quarkonium with nuclei is studied in the $m_Q\to \infty$ limit of QCD, where the binding energy is found to be exactly computable. The dominant contribution to the interaction is from two-gluon operators. The forward matrix elements of these two-gluon operators can be determined from the QCD scale anomaly, and from deep inelastic scattering. We apply our results to the ${\rm Y}$ and $J/\psi$, treating the $\text{qqbar}$ interaction as purely Coulombic. We find the ${\rm Y}$ binds in nuclear matter with a binding energy of a few $\text{mev}$, while for the $J/\psi$ binding is of order 10 $\text{mev}$. For the $J/\psi$ in particular we expect confinement effects to produce large corrections to this result.

Comments: (10 pages)