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The DC-SRF photocathode gun, an important member of superconducting radio-frequency (SRF) guns, is a distinguished compact mega-electron-volt (MeV) electron source capable of generating picosecond to sub-picosecond electron pulses at megahertz (MHz) and higher repetition rate.

2015年10月21日 · To obtain low-emittance electron beams with high average current, superconducting radio frequency photocathode guns have been developed by several laboratories worldwide. A DC-SRF injector, which combines a DC pierce gun and a superconducting cavity, has been developed at Peking University.

展开更多 直流-射频超导 (direct current-superconducting radio frequency,DC-SRF)光阴极电子枪是由北京大学射频超导加速器实验室提出并发展的一种连续波电子源,可产生MHz及以上重复频率、皮秒至亚皮秒脉冲、Me V能量的电子束.作为一类重要的超导型光阴极电子枪,DC-SRF将具有高量子效率的半导体光阴极与射频超导加速腔分离,成功地解决了二者之间的兼容问题,并具有结构紧凑、暗电流低等优点.DC-SRF光阴极电子枪的研发经历了样机、DC-SRF-I及DC-SRF-II三个阶段, …

2022年3月1日 · To obtain a low emittance, high current electron beam, a bialkali photocathode (K-Cs-Sb) was adopted in an upgraded DC-SRF photoinjector at Peking University. Based on the design and manufacture of the preparation and transport systems, a study of the K-Cs-Sb photocathode deposition and an electron beam performance test was carried out.

DC-SRF光阴极电子枪的研发经历了样机、DC-SRF-I 及DC-SRF-II 三个阶段, 其中, DC-SRF-I 于2014 年实现稳定载束运行, 并开展了系列应用实验; DC-SRF-II 于2021 年建成, 2022 年实现100 pC 束团电荷量、1 MHz 重复频率的连续波模式运行, 暗电流小于1 pA,归一化发射度达到亚mm-mrad 级, 综合性能指标处于领先地位. 本文总结DC-SRF 电子枪的研究工作, 主要内容包括DC-SRF-I 电子枪、DC-SRF-II 电子枪、 光阴极与驱动激光等.

Abstract: We present the design of a 100 W high repetition rate photocathode drive laser system for realizing high average current operation of the superconducting accelerator at Peking University. To achieve good beam quality and reliability, we choose photonic crystal fiber (PCF) as the gain medium of the main amplification unit.

DC-SRF electron injector, which combines a DC Pierce gun and a 3.5-cell 1.3 GHz superconducting cavity in a cryomodule, has been developed at Peking University. Based on the improvements of beam line, LLRF system and 2K cryogenic system, stable operation of the DC-SRF injector has been carried out recently.

2022年2月23日 · 2021 年，第二代 DC-SRF 光阴极注入器成功实现重复频率为 1 MHz 的连续波（CW）模式运行，并首次获得亚微米级归一化发射度的电子束。 北京大学物理学院副教授，重离子物理研究所副所长，中国粒子加速器学会理事。 本科就读于北京大学技术物理系原子核物理专业，硕士、博士就读于北京大学物理学院核技术及应用专业。 2005-2007、2008、2012年美国Duke大学物理系访问学者，从事储存环FEL研究。 2014年美国SLAC国家加速器实验室访问 …

Stable operation of the DC-SRF injector(1.3 GHz) has achieved. The compatibility between cathode material and superconducting cavity can be solved by using the DC-SRF structure