Dose Rate Calibration of a Commercial Beta-Particle Irradiator Used In Archeological and Geological Dating

Bernal, S. M.

Oak Ridge National Laboratory

关键词: Calibration;    Aluminium;    Irradiation;    Ceramics;    Dose Rates;   

DOI  :  10.2172/899757
RP-ID  :  ORNL/TM-2004/193
RP-ID  :  DE-AC05-00OR22725
RP-ID  :  899757

美国|英语

来源: UNT Digital Library

【 摘 要 】

The 801E Multiple Sample Irradiator, manufactured by Daybreak Nuclear Systems, is capable of exposing up to 30 samples to beta radiation by placing each sample one by one directly beneath a heavily shielded ceramic Sr-90/Y-90 source and opening a specially designed shutter. Daybreak Nuclear Systems does not provide the {sup 90}Sr/{sup 90}Y dose rate to the sample because of variations of up to 20% in the nominal activity of the beta sources (separately manufactured by AEA Technology). Thus it is left to the end user to determine. Here aluminum oxide doped with carbon (Al{sub 2}O{sub 3}:C), in the form of Landauer's Luxel{trademark}, was irradiated to different known doses using a calibrated {sup 90}Sr/{sup 90}Y beta particle irradiator, and the OSL signal monitored after each irradiation to generate a calibration curve. Comparison of the OSL Signal from the unknown 801E Irradiator dose with the calibration curve enabled the dose and therefore dose rate to be determined. The timing accuracy of the 801E Irradiator was also evaluated and found to be +/- 0.5 seconds. The dose rate of the beta source was found to be 0.147 +/- 0.007 Gy/s.