Bremsstrahlung Suppression due to the LPM and Dielectric Effects in a Variety of Materials

TL;DR

This paper investigates how bremsstrahlung emission from high-energy electrons is suppressed in various materials due to the LPM and dielectric effects, with detailed measurements across a broad photon energy range.

Contribution

It provides a comprehensive experimental analysis of bremsstrahlung suppression effects in different materials, highlighting the importance of finite thickness in thin targets.

Findings

Suppression observed aligns with theoretical predictions for most targets.

Finite thickness effects significantly influence bremsstrahlung in thin targets.

The study covers a wide photon energy range from 200 keV to 500 MeV.

Abstract

The cross section for bremsstrahlung from highly relativistic particles is suppressed due to interference caused by multiple scattering in dense media, and due to photon interactions with the electrons in all materials. We present here a detailed study of bremsstrahlung production of 200 keV to 500 MeV photons from 8 and 25 GeV electrons traversing a variety of target materials. For most targets, we observe the expected suppressions to a good accuracy. We observe that finite thickness effects are important for thin targets.