Shanghai laser electron gamma source (SLEGS) is an energy-variable gamma-ray source developed based on the inverse Compton scattering of 10640 nm photons from a 100 W CO${}_2$ laser on 3.5 GeV electrons from the Shanghai Light Source. It produces gamma-rays in the energy range of 0.4–21.7 MeV with a flux of 10${}^5$–10${}^7$ photons/s. A collimator system was designed to produce quasimonochromatic gamma-ray beams with a best possible bandwidth of 1.1%–4.4% and filter out the substandard gamma-rays. The collimator system composed of coarse and fine collimators, constitutes a critical component of the SLEGS. By Geant4 simulations, we show that the collimator system is effective in tuning beam bandwidths and regular dodecagonal beam spots at the target position.

上海激光电子伽马源 (SLEGS) 是一种能量可变伽马射线源，基于来自 100 W CO 的 10640 nm 光子的逆康普顿散射而开发${}_2$来自上海光源的 3.5 GeV 电子激光。它产生能量范围为 0.4-21.7 MeV 的伽马射线，通量为 10${}^5$–10${}^7$光子/秒。准直器系统旨在产生具有 1.1%–4.4% 的最佳带宽的准单色伽马射线束，并滤除不合格的伽马射线。由粗准直器和细准直器组成的准直器系统构成了 SLEGS 的关键部件。通过 Geant4 模拟，我们表明准直器系统在调整光束带宽和目标位置的规则十二边形光束点方面是有效的。