Prototype testing and algorithm development for the Cosmic Ray Inspection and Passive Tomography (CRIPT) project

The Cosmic Ray Inspection and Passive Tomography (CRIPT) collaboration has completed the testing of small muon detector prototypes and has commenced construction of a 12 layer, 4m
²
prototype muon scattering tomography system. Three areas of CRIPT's progress are reported: (1) results from the testing of one of drift chamber muon detector prototypes; (2) algorithms for muon momentum estimation and tomographic image reconstruction; and (3) the status of the large prototype construction. The intrinsic resolution of the 2.4 m long, 1.2 m wide drift chamber muon detector prototype has been measured to be 1.73 mm perpendicular to the anode wire, and 2.9 mm parallel to the anode. A Bayesian estimator algorithm has been developed for muon momentum estimation. From simulations, the momentum resolution is expected to be highly asymmetric, varying from −18% to +92% integrated across the cosmic ray muon spectrum. A novel Point-of-Closest-Approach (PoCA) algorithm has also been developed for tomographic imaging. Multiple possible muon trajectories are assumed for each muon. The expected completion date for the construction is summer 2012, with first tomographic data following soon afterward.