Abstract
The photoluminescence of BaO powders has been studied at temperatures between 103 and 423 K. A luminescence band peaking at 2.92 eV is observed by exciting the samples with light in the region of exciton bands. A bimolecular decay process of this 2.92 eV luminescence is observed at room temperature. This process is interpreted in terms of the thermal dissociation of excitons.