Scintillator

Material which glows when excited by ionizing radiation

A scintillator is a material that exhibits scintillation, the property of luminescence, when excited by ionizing radiation. Luminescent materials, when struck by an incoming particle, absorb its energy and scintillate. Sometimes, the excited state is metastable, so the relaxation back down from the excited state to lower states is delayed. The process then corresponds to one of two phenomena: delayed fluorescence or phosphorescence. The correspondence depends on the type of transition and hence the wavelength of the emitted optical photon.

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