Abstract:
:We propose a new method based on statistical analysis technique to determine the minimum setup distance of a well chamber used in the calibration of 192Ir high dose rate (HDR). The chamber should be placed at least this distance away from any wall or from the floor in order to mitigate the effect of scatter. Three different chambers were included in this study, namely, Sun Nuclear Corporation, Nucletron, and Standard Imaging. The results from this study indicated that the minimum setup distance varies depending on the particular chamber and the room architecture in which the chamber was used. Our result differs from that of a previous study by Podgorsak et al. [Med. Phys. 19, 1311-1314 (1992)], in which 25 cm was suggested, and also differs from that of the International Atomic Energy Agency (IAEA)-TECDOC-1079 report, which suggested 30 cm. The new method proposed in this study may be considered as an alternative approach to determine the minimum setup distance of a well-type chamber used in the calibration of 192Ir HDR.
journal_name
Med Physjournal_title
Medical physicsauthors
Chang L,Ho SY,Chui CS,Lee JH,Du YC,Chen Tdoi
10.1118/1.2911156subject
Has Abstractpub_date
2008-06-01 00:00:00pages
2214-7issue
6eissn
0094-2405issn
2473-4209journal_volume
35pub_type
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