Characterization of long-term stability of thallium bromide detectors

Abstract Thallium bromide (TlBr) gamma ray detectors exhibit excellent spectroscopic performance at room temperature. Long-term stability is an essential property for the practical application of detectors. In this study, the long-term stability of the spectroscopic performance of the TlBr detectors was characterized by acquiring 137 Cs gamma-ray spectra at room temperature. TlBr detectors were fabricated from zone-purified TlBr crystals by constructing Tl electrodes. The TlBr detectors demonstrated stable spectroscopic performances for 1000 h operations at room temperature without bias polarity switching. The peak positions for the 662 keV gamma rays remained within ±1% of the average values for the 1000 h measurements. The detectors exhibited energy resolutions of ≤4.0% full width at half maximum for 662 keV gamma rays for 1000 h acquisitions without pulse height corrections. These results suggest that TlBr detectors with Tl electrodes are potential gamma-ray detectors for practical applications.