Study of Space-charge Waves in a Long Solenoid Channel

Title of Thesis: STUDY OF SPACE-CHARGE WAVES IN A LONG SOLENOID CHANNEL Kai Tian, Master of Science, 2005 Thesis Directed By: Professor Patrick O'Shea Department of Electrical and Computer Engineering In this thesis, studies of the dynamics of longitudinal space-charge waves in space-charge dominated beams propagating through a transport channel with a long solenoid are performed. First, some basic models of space-charge waves behaviors are reviewed. Second, WARP simulations on generating either pure fast waves or pure slow waves are presented. Then experimental studies on the energy modulations converted from density modulations are reported. By changing the working conditions of the electron gun, pure initial density modulations are generated. Energy perturbation waveforms are measured by a high resolution energy analyzer. Finally, the experimental results are compared with both the linear theory and the WARP simulation results. Good agreements are achieved for the relationship between the energy and current perturbation strengths. The notable exception is a large discrepancy between experiment and theory for the speed of sound at differing perturbation strengths, which remains to be investigated in future work. STUDY OF SPACE-CHARGE WAVES IN A LONG SOLENOID CHANNEL