Radiopurity Study of an Encapsulated CeBr3 Crystal

We report on the investigation of the intrinsic activity of a commercially available CeBr3 inorganic cylindrical scintillator, 30 mm in diameter and 30 mm in height. The study has been performed by measuring gamma emissions from the encapsulated crystal at the ultralow level radioactivity laboratory at the Laboratorio Subterraneo de Canfranc (LSC). Our study shows that only traces of the primordial Radium chain ( 238 U) and more weakly from the Thorium chain ( 232 Th) are present, whereas none of the other natural background chains were detected. We have not found neutron activation products such as 82 Br or 139 Ce either, but traces of 138 La are observed. The low intrinsic activity makes the CeBr3 crystal suitable for gamma-ray spectroscopy applications requiring the detection of low intensity emissions.