Mutual dressing of bare relativistic heavy ions during transit in collider orbits. I. General considerations

In the interaction regions of a relativistic heavy-ion collider, bare, highly charged nuclei pass at great velocities, oppositely moving similar nuclei. Each nucleus, then, sees strong, time varying electromagnetic fields, and it is not surprising that there is a large probability for electron-positron pair creation (a process evaluated many years ago). There is also a smaller probability that the electron of the pair is created, not in a continuum state, but in one of the bound orbits, the K or L or higher orbits, of the Coulomb field of the previously bare nuclei. This dressing is most unfortunate for a collider device, since the charge change leaves the nucleus in an orbit that is no longer appropriate for continuing circulation. This note evaluates the probability for such dressing, and also examines whether a subsequent sweep-off process can undo the first step with any sizeable likelihood. 3 references