| Autor: |
Desrosiers MF; National Institute of Standards and Technology, Gaithersburg, MD 20899., Forney AM; National Institute of Standards and Technology, Gaithersburg, MD 20899., Puhl JM; National Institute of Standards and Technology, Gaithersburg, MD 20899. |
| Jazyk: |
angličtina |
| Zdroj: |
Journal of research of the National Institute of Standards and Technology [J Res Natl Inst Stand Technol] 2012 May 02; Vol. 117, pp. 143-53. Date of Electronic Publication: 2012 May 02 (Print Publication: 2012). |
| DOI: |
10.6028/jres.117.007 |
| Abstrakt: |
The dosimeters used to monitor industrial irradiation processing commonly experience significant temperature rises that must be considered in the dose analysis stage. The irradiation-temperature coefficient for a dosimetry system is derived from the dosimeter's radiation response to the absorbed dose and the irradiation temperature. This temperature coefficient is typically expressed in percent change per degree. The temperature rise in dosimeters irradiated with high-intensity ionizing radiation sources can be appreciable. This is especially true for electron-beam processing in which dosimeter temperatures can approach 80 °C. A recent National Institute of Standards and Technology (NIST) study revealed modest (0.5 % to 1.0 %) deviations from the predicted value at temperatures above 70 °C for absorbed doses of 1 kGy and 20 kGy. However, these data were inconsistent with a concurrent manuscript published by National Physical Laboratory (NPL) researchers that found a significant dose-dependent non-linear alanine response but used dosimeters from a different manufacturer and a different experimental design. The current work was undertaken to reconcile the two studies. Alanine dosimeters from each manufacturer used by NIST and NPL were co-irradiated over a wide range of absorbed dose and irradiation temperature. It was found that though there was a slight variation in the temperature coefficient between the two alanine dosimeter sources both systems were linear with irradiation temperature up to 70 °C and the NPL observations of non-linearity were not reproduced. These data confirmed that there is no fundamental difference in the two commercial alanine dosimeter sources and that temperature corrections could be made on industrial irradiations at the extremes of irradiation temperature and absorbed dose. |
| Databáze: |
MEDLINE |
| Externí odkaz: |
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