The space radiation environment is a critical bottleneck restricting the safety and reliability of space activities, posing a severe threat to the stable operation of on-orbit satellites and spacecraft electronic equipment, as well as the life and health of astronauts. With the rapid development of space exploration and aerospace applications, research on the space radiation environment and its effects has become increasingly strategically significant for ensuring space mission safety and improving the in-orbit reliability of spacecraft.
Laser-driven electron beams have important application value in the field of space radiation environment simulation. However, the direct laser irradiation of high-density solid targets produces electron beams with poor spectral tunability and high laser energy requirements, which limits their wide application. In this work, a scheme is proposed to simulate orbital electron radiation in near-Earth space using laser-driven electron acceleration with a dual-plane composite target^[1]. It is found that high-density solid Target II can supply a large number of low-energy electrons, while the low-density planar Target I located in front of Target II can provide a small number of high-energy electrons, making the resulting electron energy spectrum very close to that of the actual space radiation environment.
To evaluate the similarity between the generated energy spectrum and the space radiation spectrum, an energy spectrum similarity evaluation method is proposed, which can characterize both local and global spectral similarity. For low-density planar Target I, electron acceleration is dominated by laser ponderomotive acceleration with half-wavelength oscillation. As the target density increases, the acceleration mechanism gradually transitions from laser ponderomotive acceleration to surface ponderomotive acceleration, and the electron beam energy spectrum is effectively modulated. The optimal target parameters are obtained via Bayesian optimization, and the generated electron beam shows much better matching with the space radiation environment. The results provide a theoretical reference for experimental studies on simulating space radiation environments in different orbits using laser-driven electron beams.
Based on the above novel laser-plasma radiation source, we systematically carried out electron radiation effect experiments^[2] on two-dimensional layered FePS₃. It is verified that high-energy broad-spectrum electron beams can induce crystal-to-amorphous transition, interlayer cleavage, and surface etching of the material, resulting in the breakage of P–P and P–S bonds and significant attenuation or even disappearance of characteristic Raman peaks. Moreover, the radiation damage becomes more severe as the material thickness decreases. Preliminary research on the damage effects of laser-generated proton beams on optoelectronic devices has also been performed. The relevant results provide key theoretical and experimental support for the development of desktop multi-beam radiation sources, accurate simulation of space radiation environments, and radiation reliability evaluation of novel semiconductor devices.
 

laser plasma interaction,energetic electron,radiation