COLLECTIVE PHENOMENA IN ACCELERATORS

Abstract

Recent years have witnessed the development of accelerators of ever-larger current, both peak and average, as well as a proliferation of storage rings of ever-greater luminosity. Consequently, there is considerable interest in and growing concern with, the phenomena which limit beam currents and beam densities, namely, the collective modes of behavior of relativistic particle beams. Furthermore, it has been demonstrated that the collective behavior can be controlled, at least to some extent, turned to good advantage, and employed for collective acceleration in devices such as the electron ring accelerator. Quite naturally then, almost every accelerator conference during the last five years has had a review paper on collective effects, while at the same time the number of original papers in this area now exceeds many hundreds. And thus I am faced with the dilemma of being unable to give a comprehensive and complete review (such a review, incidentally, would be most valuable; in my judgment the time is ripe for a comprehensive monograph on the subject.), and yet finding it difficult, in a brief review, to be comprehensible, balanced, and yet fresh. I have resolved the dilemma by firstly supplying sufficient references as to allow the interested reader to readilymore » approach and efficiently attack the literature. Secondly, I take a few steps away from the details and the realities of the field and with the advantage of the broader view so gained, describe the basic many-body physics underlying the subject. Thirdly, I present a few examples of collective behavior, in part to make the general remarks concrete, but in large measure in order to illustrate the beauty of this kind of physics. Finally, I make some remarks on methods for control of undesirable collective behavior, and on the present state of understanding of the field.« less