What phenomenon occurs when a detector continues to glow after radiation is turned off?

The phenomenon that occurs when a detector continues to glow after the radiation source has been turned off is known as afterglow. Afterglow refers to the persistent luminescence observed in certain materials due to the excitation of atoms or ions that remain in an excited state for a brief period after the radiation exposure has ceased.

In the context of detectors used in medical imaging, including CT, this can impact image quality as the residual light from afterglow could potentially interfere with the clarity of the images being produced. The material’s properties, energy levels, and the duration of the afterglow are crucial in determining how significant this effect could be on the imaging results.

The term “residual scintillation” may sound similar but specifically refers to the light emitted by scintillation materials that temporarily remain luminous until they fully return to their unexcited state, which is generally a part of the afterglow phenomenon. “Post-irradiation luminescence” is a broader term that encompasses various types of luminescence that occur after exposure but does not specifically denote the persistent glowing nature that is characterized by afterglow. Finally, "phosphorescence" involves a delayed re-emission of light, but it is a different mechanism that