Response of CsI (T1) Crystals to Energetic Particles

Abstract

The light output of thallium-activated cesium iodide was measured as a function of bombarding energy for protons ($240 \mathrm{kev}<~{E}_{p}<~2550 \mathrm{kev}$), alpha particles ($980 \mathrm{kev}<~{E}_{\ensuremath{\alpha}}<~4920 \mathrm{kev}$), and ${\mathrm{C}}^{12}$ ions ($320 \mathrm{kev}<~{E}_{\mathrm{C}}<~1850 \mathrm{kev}$). The relation of the light output to the particle energy is approximately linear in these energy ranges. The light outputs for different particles of the same energy are in the ratio $p:\ensuremath{\alpha}:{\mathrm{C}}^{12}=1.00:0.59:0.35$. Saturation effects account for these results. The resolution varies inversely as the square root of the light output.