X-ray Excited Luminescence Yield Spectra of NaBr and NaBr:Cu Single Crystals

X-ray excited optical luminescence yield spectra of single crystals of pure NaBr and Cu-activated NaBr are reported. X-rays are scanned at the energy regions of K edges of Br and Na. The yield spectra for the intrinsic luminescence emission band of NaBr at 4.5 eV for both samples and those for the Cu impurity luminescence band at 3.4 eV are compared. The results show that in the NaBr:Cu, both positive and negative edge jumps are observed depending on the monitored emission band. The yield spectra are reproduced with the calculation following our recent phenomenological theory.