The proton energy response of a LYSO crystal

We measured the energy response of a LYSO (Lu_2(i-x)Y _2xSiO₅) crystal by using a proton beam. The LYSO crystal has good performances, such as a fast decay time, a high light output and radiation hardness and it is widely used for nuclear physics and medical imaging. The experiment was carried out in the MC-50 cyclotron at the Korea Institute of Radiological and Medical Sciences (KIRAMS) by using 35 and 45 MeV proton beams. Different thicknesses of Al degraders were used with the 35 and the 45 MeV proton incident energies to measure the light output response function of the LYSO crystal. The results were calibrated with a ¹³⁷Cs 7-ray source for the different energy response of the LYSO and were compared with the proton energy calibrated by using the SRIM code, which is a well-known stopping-range calculation code. This is the first time for measuring the response function of the LYSO crystal with a proton beam.