Modulational instabilities within the thermal wave model description of high energy charged particle beam dynamics

Within the thermal wave model (TWM) description, an investigation was made of the longitudinal instability properties of a coasting high energy charge d particle beam, where thr interaction between the beam and its surrounding s is characterized in terms of a complex impedance. The analysis is shown t o correctly reproduce the characteristic features of the coherent instabili ty as obtained previously by conventional techniques based on the Vlasov eq uation for the beam distribution. The results further validate the TWM appr oach as a consistent alternative description for analyzing the dynamics of high energy charged particle beams. (C) 1999 Published by Elsevier Science B.V. All rights reserved.