Experimental determination of the dose deposition profile of a Sr-90 beta source

GAZA R., Bulur E., McKeever S. W. S., Soares C. G.

RADIATION PROTECTION DOSIMETRY, vol.120, pp.33-37, 2006 (SCI-Expanded) identifier identifier identifier

  • Publication Type: Article / Article
  • Volume: 120
  • Publication Date: 2006
  • Doi Number: 10.1093/rpd/nci654
  • Journal Name: RADIATION PROTECTION DOSIMETRY
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.33-37
  • Middle East Technical University Affiliated: Yes

Abstract

Three different methods for characterising the dose deposition profile of a Sr-90/Y-90 radioactive source are described: GAFChromic film dosimetry, Thermoluminescence (TL) and Optically Stimulated Luminescence (OSL). For the film measurements, GAFChromic film samples were stacked at different depths between polyethylene terephthalate (PET) foils. For TL, the thickness of a TLD-500 dosemeter was gradually reduced by polishing and the TL from chips of different thickness was used in conjunction with a mathematical model based on the exponential attenuation of dose inside the crystal to determine the decay constant for the dose-depth profile. Finally, an OSL reader with confocal stimulation / detection capabilities was used to map the two-dimensional dose distribution in TLD-500 dosemeters as a function of depth. The shapes of the dose deposition profiles obtained from all the investigated methods are in good agreement.