Beam observation and the nature of instabilities

Abstract

In this manuscript ... we will rather dwell on the various means which have been invented to observe the beams, to track and record their most intimate behavior in order to assess their margin of stability, and finally through a better understanding of their properties to devise ways of increasing the machine performance. Although in this exercise good theories are a necessary ingredient, we will put more emphasis on the almost ‘intuitive’ understanding of the nature of the fundamental phenomena at work. The first chapter will describe the observable manifestations of an ensemble of particles with no interactions between them. The second and third chapters will study the effect of wake fields on the collective behavior of the beam particles. The basic nature of beam instabilities will be shown with the help of simple examples. (AIP)