Color Transparency and Charmonium Photoproduction

We discuss the effect of “color transparency” on J/ψ, ψ′, and χ photoproduction off nuclear targets. We find (contrary to the conclusion of other authors) that it is not an important effect for J/ψ production at present energies, so that existing experimental extractions of${\mathrm{\sigma }}_{\mathrm{\psi }\mathrm{N}}$ should be reliable. It may, however, be important when determining ${\mathrm{\sigma }}_{\mathrm{\psi }\prime \mathrm{N}}$ and${\mathrm{\sigma }}_{\mathrm{\chi }\mathrm{N}}$. © 1990 The American Physical Society