Diffusion mechanism of particle beams in the presence of phase modulation in double RF systems

Author

Ball, M. ; Budnick, J. ; Chu, C.M. ; Fung, K.M. ; Hamilton, B. ; Jeon, D. ; Kang, X. ; Kiang, L.L. ; Lee, S.Y. ; Pei, A. ; Sloan, T. ; Ng, K.Y.

Author_Institution

Indiana Univ., Bloomington, IN, USA

Volume

3

fYear

1999

fDate

1999

Firstpage

1545

Abstract

The particle diffusion mechanism due to phase modulation on one of the RF cavities in a double RF system is studied. We find that the Einstein relation is satisfied if there is a global chaos in the phase space. On the other hand, the existence of dominant parametric resonances forces the particles streaming along the separatrix, which may result in an anomalous diffusion process. The particle tracking simulations based on the Hamiltonian for the double RF system is employed to reveal the essential diffusion mechanism. Also for the first time, a coherent octupole mode has been observed in the bunch beam excitation. The phase space evolution of the octupole mode is displayed

Keywords

accelerator RF systems; accelerator cavities; chaos; particle beam bunching; particle beams; phase modulation; Einstein relation; RF cavities; anomalous diffusion; bunch beam excitation; coherent octupole mode; dominant parametric resonances; double RF systems; global chaos; octupole mode; particle beams; particle diffusion mechanism; particle tracking simulations; phase modulation; phase space evolution; Chaos; Diffusion processes; Particle beams; Particle tracking; Phase modulation; Physics; Radio frequency; Stochastic processes; Synchrotrons; Voltage;

fLanguage

English

Publisher

ieee

Conference_Titel

Particle Accelerator Conference, 1999. Proceedings of the 1999

Conference_Location

New York, NY

Print_ISBN

0-7803-5573-3

Type

conf

DOI

10.1109/PAC.1999.794162

Filename

794162