PRIMA results on proton imaging

The PRIMA experiment, funded by INFN Italy, is aimed at developing a proton Computed Tomography prototype based on tracking single protons. It consist in the use of silicon microstrip detectors to measure the position and direction of individual protons before and after they traverse the phantom, and a calorimeter for measuring particle residual energy. A small prototype with a field of view of 5 x 5 cm2 was tested, under 60 MeV and 180 MeV proton beams. In this paper the experiments concerning proton imaging will be presented. Reconstructed images show the good performances of the device, with spatial resolution fulfilling the stringent requirements of a pCT device and demonstrate the validity of the working principles of pCT in a small scale prototype.