Numerical simulation on generation and propagation of vortex synchrotron radiation

It was theoretically shown that a single free electron in circular/spiral motion emits optical vortex. Such process can be found in relativistic electron beam crossing a helical undulator and the emitted radiation is known as undulator radiation. We have carried out experimental studies to characterize the synchrotron radiation at the UVSOR-III electron storage ring. We also have performed numerical simulations of the radiation process using a code Synchrotron Radiation Workshop (SRW), widely used in the synchrotron radiation community. The simulation reproduces the radiation properties very well. The simulation is expected to predict further characteristics of undulator radiation as optical vortex.