Cosmic ray muon computed tomography of spent nuclear fuel in dry storage casks

TL;DR

This paper demonstrates that cosmic ray muon scattering tomography, combined with filtered back projection algorithms, can effectively image and verify the contents of spent nuclear fuel in dry storage casks within two days, enhancing nuclear security.

Contribution

It introduces the application of medical imaging algorithms to cosmic ray muon imaging for nuclear material verification in dry storage casks, validated through GEANT4 simulations.

Findings

High-confidence verification of cask contents within two days

Effective tomographic imaging with a surrounding cylindrical detector

Potential for portable, multi-angle detector configurations

Abstract

Radiography with cosmic ray muon scattering has proven to be a successful method of imaging nuclear material through heavy shielding. Of particular interest is monitoring dry storage casks for diversion of plutonium contained in spent reactor fuel. Using muon tracking detectors that surround a cylindrical cask, cosmic ray muon scattering can be simultaneously measured from all azimuthal angles, giving complete tomographic coverage of the cask interior. This paper describes the first application of filtered back projection algorithms, typically used in medical imaging, to cosmic ray muon imaging. The specific application to monitoring spent nuclear fuel in dry storage casks is investigated via GEANT4 simulations. With a cylindrical muon tracking detector surrounding a typical spent fuel cask, the cask contents can be confirmed with high confidence in less than two days exposure. Similar results can be obtained by moving a smaller detector to view the cask from multiple angles.