

Pure cesium iodide (pure CsI) is a fast-response inorganic scintillation crystal with two main emission bands: a fast component peaking at 315 nm in the near-ultraviolet region and a secondary emission at 460 nm. It features an extremely short scintillation decay time of ~16 ns, much faster than most doped CsI variants, plus strong radiation resistance and a high density of 4.51 g/cm³. These properties make it ideal ...
Pure cesium iodide (pure CsI) is a fast-response inorganic scintillation crystal with two main emission bands: a fast component peaking at 315 nm in the near-ultraviolet region and a secondary emission at 460 nm. It features an extremely short scintillation decay time of ~16 ns, much faster than most doped CsI variants, plus strong radiation resistance and a high density of 4.51 g/cm³. These properties make it ideal for fast timing applications such as electromagnetic calorimeters in high-energy physics experiments.
OST Photonics specializes in supplying customized pure CsI crystals for research institutes and university laboratories, supporting tailored specifications to meet the unique requirements of academic and scientific research projects.
Fast electromagnetic calorimeters in high-energy and nuclear physics experiments
Cosmic ray detection in space exploration
Industrial high-speed radiation imaging and non-destructive testing systems
Particle identification and trigger systems for large accelerator experiments
Extremely short scintillation decay time
High material density (4.51 g/cm³)
Good radiation resistance
Good mechanically characteristics
Maximum Size: ɸ90mm x 300mm
Available items: monolithic crystal
Relative Light Output of NaI(Tl) (%) | 4~6% |
Scintillation Decay Time (ns) | 16 |
Emission Peak Wavelength (nm) | 315 |
Refractive Index (peak wavelength) | 1.95 |
Density(g/cm3) | 4.51 |
Hygroscopic | Slight |
Mohs hardness | 2 |
Afterglow | — |
Light yield (photons/keV) | 2 |

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