Publication Date
2026
Document Type
Dissertation/Thesis
First Advisor
Ha, Gwanghui
Degree Name
M.S. (Master of Science)
Legacy Department
Department of Physics
Abstract
Electron beam chirping for bunch compression is commonly achieved through off-crest acceleration in radio-frequency accelerating cavities. While it is effective, this method reduces average beam energy and introduces nonlinearities in the beam's longitudinal phase space, which can degrade beam quality in applications such as X-ray free electron lasers. An alternative chirping scheme has been proposed, in which accelerating cavities operate on-crest while transverse deflecting cavities generate the required longitudinal chirp. However, the efficiency of this approach and its impact on beam quality have not been systematically investigated, and the previously proposed dechirping scheme for this system is experimentally impractical. This thesis presents an analytical study of the efficiency of the transverse deflecting cavity chirper and compares it with the conventional chirping method. A dechirping method based on forming negative-identity drifts between chirper cavities is also proposed. Analytical and simulation studies are performed to evaluate the performance of the proposed dechirper, including its response to varying beam parameters, and provide a detailed analysis of beam quality degradation from nonlinear effects along with an emittance growth mitigation strategy. To support a future experimental demonstration at the Argonne Wakefield Accelerator, a start-to-end simulation is conducted to characterize the dechirper under realistic beam conditions. The results demonstrate that the proposed dechirper can effectively control chirp while preserving beam quality, which indicates its potential as an alternative approach that improves efficiency, reduces system length, and provides linear control of the longitudinal chirp.
Recommended Citation
Desimone, Alex, "Longitudinal Dechirping of Electron Beams Using Negative Identity Drifts in a Transverse Deflecting Cavity-Based Chirper" (2026). Graduate Research Theses & Dissertations. 8198.
https://huskiecommons.lib.niu.edu/allgraduate-thesesdissertations/8198
Extent
63 pages
Language
en
Publisher
Northern Illinois University
Rights Statement
In Copyright
Rights Statement 2
NIU theses are protected by copyright. They may be viewed from Huskie Commons for any purpose, but reproduction or distribution in any format is prohibited without the written permission of the authors.
Media Type
Text
