Used in radiation detection due to its high density and ability to efficiently absorb gamma rays and X-rays. Commonly found in scintillation counters where it emits light when exposed to ionizing radiation, allowing for precise measurement in medical imaging, nuclear power plants, and scientific research. Also used in infrared spectroscopy as optical components because of its transparency in the infrared range. Thin films of cesium iodide serve in particle physics detectors and electron multipliers for its low work function and photoemissive properties.