强激光与粒子束, 2012, 24 (1): 197, 网络出版: 2012-02-14
外注入式独立调谐微波电子枪的概念设计
Conceptual design of independently tunable cells RF gun with external injecting structure
热发射 独立调谐腔 外注入式 束团压缩 预注入器 thermionic independently tunable cell external injecting bunch length compression pre-injector
摘要
为得到微脉冲束团长度在百fs量级且高重复频率, 设计了一种紧凑型的强流电子枪结构--独立调谐微波热发射电子枪。该电子腔具有双驻波加速腔, 两个驻波加速腔之间相互没有耦合, 可以分别独立地馈入功率、调节相位。通过优化功率与相位, 可以得到较优的束流品质, 同时避免了α磁铁和激光系统的使用, 使得结构更加紧凑。并采用外注入式结构增大流强、降低能散度, 同时消除电子反轰对阴极的负面影响。对不同结构参数的腔体进行1维和3维束流动力学计算, 可以得到较为理想的腔体参数。通过调节预注入器的馈入功率和粒子入射相位, 可以进一步的压缩束团长度。
Abstract
To obtain the micro-pulse bunch with the order of hundred femtoseconds length and high repetition rate, the paper proposes the independently tunable cells (ITC) RF gun, which has a double-cell structure with the cells being power fed independently. By choosing appropriate feeding power and phase of the two cells, this ITC-RF gun can achieve bunches of excellent characteristics. Additionally, the application of α-magnet and laser system can be avoided, which leads to more compact layout. An external injecting ITC-RF gun (DC-ITC-RF gun) structure is designed accordingly. The external injecting structure can increase beam current, decrease energy spread, and cancel the back-bombardment effect almost completely. By means of 1-D and 3-D beam dynamics calculation with different structure parameters, a group of RF parameters are obtained for better beam characteristics. Then the paper designs a pre-injector so that particles can be accelerated to 10 MeV. By choosing appropriate feeding power and incident particle phase for the pre-injector, the bunch length can be further compressed.
梁军军, 冯光耀, 裴元吉, 庞健. 外注入式独立调谐微波电子枪的概念设计[J]. 强激光与粒子束, 2012, 24(1): 197. Liang Junjun, Feng Guangyao, Pei Yuanji, Pang Jian. Conceptual design of independently tunable cells RF gun with external injecting structure[J]. High Power Laser and Particle Beams, 2012, 24(1): 197.