CsI(Na) (Sodium-doped Cesium Iodide) is a fast, high-efficiency scintillator crystal optimized for gamma-ray spectroscopy and low-energy radiation detection. Sodium activation enhances light output while preserving faster decay time compared with CsI(Tl), making CsI(Na) suitable for moderate count-rate and timing-sensitive measurements. CsI(Na) emits primarily in the blue region (~420 nm), offering good compatibility with photomultiplier tubes (PMTs) and selected silicon-based detectors. With its high effective atomic number and density, CsI(Na) provides strong absorption efficiency for X-rays and gamma rays, enabling reliable energy discrimination in laboratory and field instruments. Compared with NaI(Tl), CsI(Na) delivers better mechanical robustness and reduced hygroscopicity, while maintaining good scintillation efficiency. These properties make CsI(Na) a practical choice for research detectors, nuclear instrumentation, and compact radiation monitoring systems. Typical Applications Gamma-ray spectroscopy Nuclear and particle physics detectors Radiation monitoring instruments University and national-lab research systems Below is a clear comparison of the properties of pure CsI, CsI:Tl, and CsI:Na: Comparison of CsI, CsI:Tl, and CsI:Na Property CsI:Tl CsI:Na Pure CsI Light Yield (photons/keV) ~56 ~40
