An electromagnetic physics constructor for low energy polarised X-/gamma ray transport in Geant4

Jeremy M.C. Brown, Matthew R. Dimmock

Research output: Contribution to journalArticleResearchpeer-review


The production, application, and/or measurement of polarised X-/gamma rays are key to the fields of synchrotron science and X-/gamma-ray astronomy. The design, development and optimisation of experimental equipment utilised in these fields typically relies on the use of Monte Carlo radiation transport modelling toolkits such as Geant4. In this work the Geant4 “G4LowEPPhysics” electromagnetic physics constructor has been reconfigured to offer a best set of electromagnetic physics models for studies exploring the transport of low energy polarised X-/gamma rays. An overview of the physics models implemented in “G4LowEPPhysics”, and it's experimental validation against Compton X-ray polarimetry measurements of the BL38B1 beamline at the SPring-8 synchrotron (Sayo, Japan) is reported. “G4LowEPPhysics” is shown to be able to reproduce the experimental results obtained at the BL38B1 beamline (SPring-8) to within a level of accuracy on the same order as Geant4’s X-/gamma ray interaction cross-sectional data uncertainty (approximately ± 5 %).

Original languageEnglish
Pages (from-to)176-182
Number of pages7
JournalNuclear Instruments and Methods in Physics Research, Section B: Beam Interactions with Materials and Atoms
Publication statusPublished - 1 Sept 2021


  • Compton scattering
  • Gamma-ray astronomy
  • Geant4
  • Polarized gamma ray
  • Synchrotron radiation facility
  • X-ray astronomy

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