An undergraduate laboratory study of the polarisation of annihilation photons using Compton scattering

TL;DR

This undergraduate experiment demonstrates photon polarisation effects in Compton scattering and explores quantum entanglement using electron-positron annihilation, with analysis supported by simulation.

Contribution

It introduces a practical undergraduate laboratory setup to study photon polarisation and quantum entanglement via Compton scattering and simulation.

Findings

Photon polarisation affects Compton scattering cross-section.

Finite geometry effects influence experimental results.

Simulation helps understand experimental limitations.

Abstract

An experiment for the advanced undergraduate laboratory which allows students to study the effect of photon polarisation in Compton scattering and to explore q\ uantum entanglement is described. The quantum entangled photons are produced through electron-positron annihilation in the $S$-state, and their polarisations a\ re analysed using the Compton scattering cross-section dependence on the photon polarisation. The equipment necessary for this experiment is available at a typ\ ical undergraduate physics laboratory. Finite geometry effects are discussed and investigated with the use of a Geant4-based simulation.