Prototype Tracking Studies for Proton CT

As part of a program to investigate the feasibility ofproton computed tomography, the most likely path (MLP) of protonsinside an absorber was measured in a beam experiment usinga silicon strip detector set-up with high position and angular resolution.The locations of 200 MeV protons were measured at threedifferent absorber depth of PolyMethylMethAcrylate-PMMA(3.75, 6.25 and 12.5 cm) and binned in terms of the displacementand the exit angle measured behind the absorber. The observedposition distributions were compared to theoretical predictionsshowing that the location of the protons can be predicted with anaccuracy of better than 0.5 mm.