Meng, Xiangyu; Wang, Yong; Shi, Xianbo; Ren, Junchao; Sun, Weihong; Cao, Jiefeng; Li, Junqin; Tai, Renzhong

JOURNAL OF SYNCHROTRON RADIATION

2023, 30, 1600-5775

Meng, Xiangyu; Wang, Yong; Shi, Xianbo; Ren, Junchao; Sun, Weihong; Cao, Jiefeng; Li, Junqin; Tai, Renzhong

The mutual optical intensity (MOI) model is a partially coherent radiation propagation tool that can sequentially simulate beamline optics and provide beam intensity, local degree of coherence and phase distribution at any location along a beamline. This paper extends the MOI model to non-ideal two-dimensional (2D) optical systems, such as ellipsoidal and toroidal mirrors with 2D figure errors. Simulation results show that one can tune the trade-off between calculation efficiency and accuracy by varying the number of wavefront elements. The focal spot size of an ellipsoidal mirror calculated with 100 x 100 elements gives less than 0.4% deviation from that with 250 x 250 elements, and the computation speed is nearly two orders of magnitude faster. Effects of figure errors on 2D focusing are also demonstrated for a non-ideal ellipsoidal mirror and by comparing the toroidal and ellipsoidal mirrors. Finally, the MOI model is benchmarked against the multi-electron Synchrotron Radiation Workshop (SRW) code showing the model's high accuracy.