3D imaging using combined neutron-photon fan-beam tomography: A Monte Carlo study

• Evaluation of fan-beam combined neutron and photon tomography.
• Neutron and photon transport was simulated using MCNP5.
• Results show that this imaging technique reveals both shape and material composition of objects.

The application of combined neutron-photon tomography for 3D imaging is examined using MCNP5 simulations for objects of simple shapes and different materials. Two-dimensional transmission projections were simulated for fan-beam scans using 2.5 MeV deuterium-deuterium and 14 MeV deuterium-tritium neutron sources, and high-energy X-ray sources, such as 1 MeV, 6 MeV and 9 MeV. Photons enable assessment of electron density and related mass density, neutrons aid in estimating the product of density and material-specific microscopic cross section- the ratio between the two provides the composition, while CT allows shape evaluation. Using a developed imaging technique, objects and their material compositions have been visualized.