Fast data acquisition in heavy ion CT using intensifying screen - EMCCD camera system

We report preliminary results for fast data acquisition in a heavy ion computed tomography (IonCT) system using an X-ray intensifying screen-charged coupled device (CCD) camera system. We recently installed a high quality Electron Multiplying CCD (EMCCD) camera, which drastically reduced data acquisition time. We also installed a parallel-plate ionization chamber upstream of an object to monitor the time variation in heavy ion beam intensity from a synchrotron accelerator and to perform beam intensity correction for all EMCCD images. Experiments were conducted using 12 C beams accelerated up to 400 MeV/u by the Heavy Ion Medical Accelerator in Chiba (HIMAC), installed at the National Institute of Radiological Sciences, Japan, in 2011. We demonstrate that an electron density phantom consisting of six rods with a diameter of 1cm was successfully reconstructed in only 14 min for 256 projections using the proposed technique with HIMAC.