Photoproduction of quarkonium in proton-proton and nucleus-nucleus collisions.

We discuss the photoproduction of Upsilon and J/psi at high energy pp, pp, and heavy ion colliders. We predict large rates in pp interactions at the Fermilab Tevatron and in pp and heavy ion interactions at the CERN Large Hadron Collider. The J/psi is also produced copiously at the Relativistic Heavy Ion Collider.

Coherent vector-meson photoproduction with nuclear breakup in relativistic heavy-ion collisions.

Relativistic heavy ions are copious sources of virtual photons. The large photon flux gives rise to a substantial photonuclear interaction probability at impact parameters where no hadronic interactions can occur. Multiple photonuclear interactions in a single collision are possible.