Dalian Advanced Light Source Pre-research Project realizes the megahertz repetition frequency electron beam current penetration experiment

Recently, the joint R&D team of Academician Yang Xueming and Researcher Zhang Weiqing of Dalian Institute of Chemical Physics, Chinese Academy of Sciences successfully realized the stable penetration experiment of 1 million Hz repetition frequency electron beam in the pre-research project of high repetition frequency extreme ultraviolet free electron laser device (hereinafter referred to as "Dalian Advanced Light Source") for the first time, which indicates that Dalian Advanced Light Source Joint Team has mastered relevant core technologies and laid a solid foundation for the construction of advanced light sources.

The Dalian Advanced Light Source Pre-research Project was launched in 2020. It is jointly undertaken by a joint R&D team composed of the Dalian Light Source Science Research Laboratory of the Dalian Institute of Chemical Physics and the Shenzhen Advanced Light Source Research Institute. It is funded and deployed by the Dalian Municipal Government. The main goal is to overcome the key core technologies of high repetition frequency and high quality electron beams.

After five years of unremitting efforts, the R&D team has successively conquered core key technologies such as photocathode electron gun, ultrafast laser system, all-solid-state radio frequency power source, superconducting accelerator, and cryogenic liquid helium system, and completed equipment installation and online independent debugging in the first half of this year. After completing half a month of joint system debugging, the joint R&D team tried to carry out a megahertz-level repetition frequency electron beam experiment, and successfully achieved stable beam output at 23:15 on July 24.

At present, the beam test platform has achieved stable accelerated operation of 0.1 mA average current intensity electron beam. Specific technical indicators include: the electron beam energy is greater than 100 million electron volts, the single pulse charge is greater than 100 picolibraries, the repetition frequency is 1 million Hz, the whole platform runs stably for 1 hour, and the beam energy stability is better than 0.01% (RMS).

The success of this experiment is of great significance to the construction and research and development of high repetition frequency free electron laser device in China.