Plasma type of instabilities in accelerators—Electron cloud and ion effects

Abstract

Plasma type instabilities are serious issue in recent high intensity accelerators. Extra-particles, ions or electrons, are created by the beam due to ionization, photoemission, secondary emission and/or other mechanisms. The beam and the extraparticles form non-neutral plasma with different collective velocities. Two-stream instability is caused by the interaction between these two beams with different velocities. We discuss general picture of the two stream instability in accelerators, especially speaking three typical effects; e-p, ion, electron clouds.