A Fast Method for Generating Synchrotron Radiation Ray Traces at the ALS

Abstract

Ray tracing for radiation safety involves defining an envelope that contains all possible ray paths, accounting for the motion range of the optics. This is required for all x-ray beamlines at the Advanced Light Source. Traditionally, it would take days for designers to manually sketch the envelope using computer-aided design. We present a MATLAB-based program that generates 3D envelope models in seconds. The program tracks light propagation in the phase space using ray transfer matrices. We compared its results against the long-established RAY-UI ray tracing program, which requires extensive computation to achieve sufficient ray sampling and motion discretization. Both techniques yield nearly the same results for quasi-flat mirrors with small motion range, with differences of less than 0.5 mm. For more complex optics, a complementary hybrid approach takes over from the ray transfer matrix method, leveraging RAY-UI’s capabilities to provide accurate yet efficient ray tracing.