Simulation and structure Design of Macro-size Accelerator Structures for CO2 Laser-driven Linear Acceleration in a Vacuum and the Structure Optical Characterization

• Main Authors: Yuan-yao, Lin, 林元堯
• Other Authors: Yen-chieh, Huang
• Format: Others
• Language: en_US
• Published: 2003
• Online Access: http://ndltd.ncl.edu.tw/handle/03138742952834376574

碩士 === 國立清華大學 === 電機工程學系 === 91 === Particle Accelerators are probes for high atomic physics research. Accelerator research integrates the most advanced technology and skills in the world with one and only one goal-to reveal the fundamentals of the universe. The contribution of conventional Radio Frequency accelerator has pushed the high energy particle to tens of GeV energy level and successfully probed the existence fundamental particles such as quarks. However, due to the field emission and material damage issue, the performance of convention Radio Frequency accelerator is saturated. The acceleration gradient can’t be pushed further. Dating back to 1960’s people suggested the application of laser as an accelerator. Efforts dedicated to this work have been made over 40 years. The work in this thesis concentrates on the design and study of structure based laser driven particle accelerator proposed and studied. In the first chapter, the basic concepts of acceleration and radiation are described. What’s more, the previous works on different laser accelerator schemes are briefly mentioned. In chapter 2, the modeling and theoretical analysis of laser acceleration are discussed. A simulation tool based on plane expansion method has been developed. With this tool two structure based laser accelerators are designed and analyzed. One is a single stage corner reflector laser accelerator, and the other is a 16-stage lens array laser linear accelerator structure. The single stage one serves as a proof of principle experiment work. The multiple-stage one is the prototype for high gradient laser linear accelerator structure in the next generation. Under the material damage issue, the copper made corner reflector structure accelerates relativistic electron from 70 MeV to 70.15MeV in a 10cm vacuum space within the accelerator. The ZnSe lens multiple-stage structure transfers 240keV energy to 70MeV relativistic electron in a 24-cm-long accelerator structure. The acceleration gradient achieved for the two structures are 1.5MeV/m and 1MeV/m. In chapter 3, we report the experiment of the optical characteristics of the accelerator structures designed. The characterization of the accelerator structures matched the designed requirement. In the last chapter, specific future direction and work are listed and under going.