Feasibility studies of the polarization of photons beyond the optical wavelength regime with the J-PET detector

TL;DR

This study demonstrates the feasibility of measuring photon polarization beyond optical wavelengths using the J-PET detector, achieving a few-degree precision with large data samples, and opens new avenues for fundamental physics research.

Contribution

The paper presents the first quantitative analysis of photon polarization measurement at 511 keV with J-PET, extending polarization studies beyond optical wavelengths.

Findings

Single event polarization resolution is about 40 degrees.

With over ten thousand events, polarization can be determined within a few degrees.

Extends polarization measurement capabilities by five orders of magnitude beyond optical wavelengths.

Abstract

J-PET is a detector optimized for registration of photons from the electron-positron annihilation via plastic scintillators where photons interact predominantly via Compton scattering. Registration of both primary and scattered photons enables to determinate the linear polarization of the primary photon on the event by event basis with a certain probability. Here we present quantitative results on the feasibility of such polarization measurements of photons from the decay of positronium with the J-PET and explore the physical limitations for the resolution of the polarization determination of 511 keV photons via Compton scattering. For scattering angles of about 82 deg (where the best contrast for polarization measurement is theoretically predicted) we find that the single event resolution for the determination of the polarization is about 40 deg (predominantly due to properties of the Compton effect). However, for samples larger than ten thousand events the J-PET is capable of determining relative average polarization of these photons with the precision of about few degrees. The obtained results open new perspectives for studies of various physics phenomena such as quantum entanglement and tests of discrete symmetries in decays of positronium and extend the energy range of polarization measurements by five orders of magnitude beyond the optical wavelength regime.