Transport of elliptic intense charged -particle beams

The transport theory of high-intensity elliptic charged-particle beams is presented. In particular, the halo formation and beam loss problem associated with the high space charge and small-aperture structure is addressed, and a novel transport theory of large-aspect-ratio elliptic beams has been developed. In a small-aperture system image-charge effects have been found to be a new mechanism for inducing chaotic particle motion, halo formation and beam loss. The rms envelope equations have been derived and analyzed for unbunched intense charged-particle beams in an alternating-gradient focusing field and a cylindrical metal pipe. Numerical results have shown that for vacuum phase advance ao < 90°, the higher-order image-charge effects on the matched and slightly mismatched beam envelopes are negligibly small for all beams with arbitrary beam density profiles (including hollow density profiles) as well as for arbitrary small apertures (including beams with large aspect ratios). However, the main unstable region for the envelope evolution with image-charge effects, which occurs for 90: < a, < 270', depending on the value of the normalized beam intensity SKI e, has been found to be narrower than its counterpart without image-charge effects.

Department dc:contributor.department

Massachusetts Institute of Technology. Dept. of Physics.

Grantor dc:publisher

Massachusetts Institute of Technology

Year dc:date.issued

2006

Author dc:creator

• Zhou, J. (Jing), 1978-

Advisor dc:contributor.advisor

• Richard J. Temkin and Chiping Chen.

• Physics.

Statement dc:rights

• M.I.T. theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission. See provided URL for inquiries about permission.

Licence dc:rights.uri

• http://dspace.mit.edu/handle/1721.1/36815
• http://dspace.mit.edu/handle/1721.1/7582

Language dc:language.iso

eng

Identifier URI

http://dspace.mit.edu/handle/1721.1/36815

OAI identifier oai:identifier

oai:dspace.mit.edu:1721.1/36815