Improving cosmic-ray tomography of shipping containers with secondary particles

Cosmic-ray tomography has emerged as a new imaging method, with applications in a variety of fields, including safety and security. The concept of this technique is most commonly based on the measurement of the transmission or scattering of muons from cosmic-ray air showers within the volume of interest. However, during the interaction of these muons and other air shower particles with the examined objects, secondary particles are produced, which can also be utilized to gain information about the material properties of target objects. This work provides improvements to a reconstruction approach based solely on secondary particles in the context of shipping container scanning. The focus of the work is the derivation of correction factors for reconstructed object properties to allow a consistent comparison of objects anywhere within the volume. This is required due to position dependent effects on the reconstructed density and position of objects resulting from different detector sensitivities to particular secondary particles.