# Ray interpretation of the transition radiation process in a waveguide

## TL;DR

This paper analyzes the transition radiation produced by a charged particle crossing a waveguide wall, demonstrating that it can be understood through geometric optics principles with rays reflecting within the waveguide.

## Contribution

It introduces a geometric optics interpretation of transition radiation in waveguides, showing that the TR field is formed by re-reflected rays following optical laws.

## Key findings

- TR rays originate from the particle entry point
- TR field is formed by multi re-reflected rays
- Rays obey geometric optics laws

## Abstract

The paper demonstrates the geometric optic properties of the transition radiation (TR) of an ultrarelativistic point-like charged particle crossing the transverse wall of a circular semi-infinite waveguide with ideally conducting walls. It is shown that the rays forming the TR field emanate from the point of entry and obey the laws of geometric optics. The TR field at the observation point is formed from geometric-optical rays multi re-reflected from the waveguide wall.

---
Source: https://tomesphere.com/paper/1906.04521