Modelling undulators in ray tracing simulations

TL;DR

This paper presents a new model integrated into SHADOW4 for accurately simulating undulator radiation in ray tracing, accounting for effects like emittance, energy spread, and diffraction, enhancing the realism of synchrotron source simulations.

Contribution

The paper introduces a comprehensive undulator radiation model in ray tracing that includes key physical effects, improving simulation accuracy for 4th generation synchrotron sources.

Findings

Model accurately simulates undulator radiation including emittance and diffraction effects.

Integration with SHADOW4 enhances existing ray tracing capabilities.

Examples demonstrate improved realism in source simulation.

Abstract

We introduce a model that can accurately simulate radiation from undulator sources for ray tracing applications. It incorporates several key effects relevant to 4$^\text{th}$ generation synchrotron sources, such as electron emittance, energy spread, and diffraction-limited beam size. This code has been developed as part of SHADOW4, the latest version of the widely used SHADOW X-ray optics ray tracing program. The approach relies on calculating the field distribution in the far field, which determines the ray divergences. The integration of existing models for electron energy spread is also addressed. Rays sampled at the source follow a size distribution derived by backpropagating the far field radiation. These models are detailed, and several examples are provided.