Transition radiation based transverse beam diagnostics for non relativistic ion beams

TL;DR

This paper explores using optical transition radiation for non-relativistic ion beam diagnostics, highlighting the potential for transverse profile measurements through observed unpolarized radiation from rough targets.

Contribution

It demonstrates the feasibility of using transition radiation from rough surfaces for beam profile diagnostics in non-relativistic ion beams, expanding applications beyond relativistic electrons.

Findings

Unpolarized transition radiation is significantly increased at grazing angles.

The radiation characteristics depend on target surface roughness.

Potential for improved transverse profile measurements using this method.

Abstract

The usage of optical transition radiation for profile monitoring of relativistic electron beams is well known. This report presents the case for beam diagnostic application of optical transition radiation for non-relativistic ion beams. The angular distribution of the transition radiation emitted from few target materials for ion beam irradiation is shown. In addition to expected linearly polarized transition radiation in the plane of observation, a large amount (roughly factor 20) of unpolarized radiation is observed towards grazing angles. The unpolarized radiation has the characteristics of transition radiation and is understood as the transition radiation generated from a "strongly" rough target surface. This increase in amount of radiation towards the detector can be used advantageously towards transverse profile measurements and potentially other beam parameters. Further systematic effects such as the dependence of photon yield on beam current, comparison of the measured transverse profiles with Secondary electron emission based grid (SEM grid), target heating etc. are also discussed.