Thermal Decay of the Luminescence of KBr

The thermal decay of the luminescence of KBr, excited by x-rays, has been investigated over a temperature range between -77° and 250°C. The intensity of the luminescence as a function of the time after irradiation can be represented by a formula of the form: $I=\Sigma \stackrel{}{n}{I}_{\mathrm{on}}\exp \left(\frac{-t}{A{e}^{\frac{{\epsilon }_n}{\mathrm{kT}}}}\right).$ The thermal activation energies ${\epsilon }_n$ have been determined.