Scintillation light pulses (flashes) are usually characterized by a fast increase of the intensity in time (pulse rise time) followed by an exponential decrease. The decay time of a scintillator is defined by the time after which the intensity of the light pulse has returned to 1/e of its maximum value. Most scintillators are characterized by more…
To detect fast changes in transmitted intensity of X-Ray beams, such as in CT scanners or luggage X-ray detectors, crystals are required exhibiting low afterglow. Afterglow is defined as the fraction of scintillation light still present for a certain time after the X-Ray excitation stops. Afterglow originates within a millisecond and can last hours in…
A scintillator is a material that exhibits scintillation, which refers to the emission of light when the material interacts with ionizing radiation. Scintillators are widely used in various fields, including radiation detection, medical imaging, and high-energy physics. Different types of scintillators exist, and some common examples include NaI (sodium iodide), LaBr (lanthanum bromide), CeBr (cerium…
There is a great variety of choices to consider. Selecting the right material, geometry, readout and electronics are only a start. See https://www.berkeleynucleonics.com/february-11th-2022-customizing-your-scintillation-detector for further reading.
Density and atomic number (Z) Light output (wavelength + intensity) Decay time (duration of the scintillation light pulse) Mechanical and optical properties Cost
Each scintillation material has a characteristic emission spectrum, with wavelength and intensity. The shape of this emission spectrum is sometimes dependent on the type of excitation (photons/particles). Emission spectra of NaI(Tl), CsI(Tl) and CeBr3, scaled on maximum emission intensity. Also a typical quantum efficiency curve of a bialkali photocathode and a Silicon Photomultiplier (SiPm) are…
Radiation damage is defined as the change in scintillation characteristics caused by prolonged exposure to intense radiation. This damage manifests itself by a decrease of the optical transmission of a crystal which causes a decrease in pulse height and deterioration of the energy resolution of the detector. Radiation damage other than radio-activation is usually partially…
The light output (number of photons per MeV gamma) of most scintillators is a function of temperature. This is caused by the fact that in scintillation crystals, radiative transitions, responsible for the production of scintillation light, compete with nonradiative transitions (no light production). In most scintillation crystals, the light output is quenched (decreased) at higher…
The most widely used scintillation material for gamma-ray spectroscopy is Sodium Iodide, NaI(Tl). It is hygroscopic and is only used in hermetically sealed metal containers to preserve its properties. All water-soluble scintillation materials should be packaged in such a way that they are not attacked by moisture. Some scintillation crystals may easily crack or cleave…
Yes – an important aspect of your product selection. See https://www.berkeleynucleonics.com/february-23rd-2022-ruggedized-detectors-customized-scintillators-field for further reading.
