Two-dimensional beam profile monitoring by using a LYSO crystal

We made a prototype two-dimensional proton beam profile monitoring system by using a LYSO scintillation crystal attached to a photomultiplier tube mounted on a 2-dimensional scanner. We measured the beam profiles of the 45-MeV proton beam from the MC-50 cyclotron at the Korea Institute of Radiological and Medical Science by using our system. We measured the energy and the flux of the proton beam simultaneously as our device moved over a 2-dimensional area of 180 × 180 mm². To measure the two-dimensional beam profile, we scanned from -90 mm to +90 mm along the x-axis, as well as along the y-axis. We also scanned the beam profile along the two diagonal lines from the point (-90, - 90) to the point (90, 90) and from the point (-90, 90) to the point (90, -90). From these measurements, we showed the possibility of our prototype system being used as a two-dimensional proton beam profile monitoring device.