ABSTRACT
The aim of the presented paper is to examine the temperature drift and its unfolding for an environmental monitor equipped with a LaBr3(Ce) detector. It is known that temperature could influence energy, shape, and efficiency calibration. Consequently, when ambient temperature changes, the full energy absorption peak moves in the resulting spectrum. Research consists of experimental and analytical parts. During research in the climatic chamber, the dependence on temperature of energy, shape, and efficiency calibration was completed. The numerical method allows generating gamma spectra for theoretical so-called binary temperature variation.
ABSTRACT
Knowledge of a radiation detector's numerical characteristics allows its energy efficiency to be calibrated theoretically for any measurement geometry. Here, energy efficiency calibration is discussed for oriented LaBr3(Ce) detectors used for in situ radiation monitoring. Vertical and horizontal detector orientations relative to the ground surface are compared using efficiency calibrations based on the detector's numerical characteristics and are equally effective. Quantitative assessment of the different measurement geometries was performed using a new analytical approach: integrated absolute full energy peak efficiency.
ABSTRACT
BACKGROUND: The calibration of the dosimetric instruments is a basis of safety of the people working with the ionization radiation. The necessity of calibration is especially important in the institutions where the open radioactive sources are used. The paper presents the abilities of CLOR's radiological protection instruments calibration facility and the important conclusions from calibrations results for group of instruments used in Nuclear Medicine Department in Poland. MATERIALS AND METHODS: The results for five types of instruments dedicated for dose rate as well as for contamination measurements were presented. Analyzes were based on the results presented at calibration certificated of chosen instruments. RESULTS: It has been shown that the calibration factor might fluctuate by 50% in period of one year for particular instrument as well as for more than 100% for two instruments of the same type. CONCLUSIONS: The presented results prove the importance of the calibration process and it is evidence that the calibration process of the radiation protection instruments should be performed periodically for the test of dose rate measurements as well as for contamination measurements abilities.