A review of the discrepancy between the in-air and in-water calibration of cobalt-60 machines.

Autor: Berkley LW, Gagnon WF, Hanson WF, Weaver KA, Shalek RJ
Jazyk: angličtina
Zdroj: Medical physics [Med Phys] 1980 Sep-Oct; Vol. 7 (5), pp. 520-4.
DOI: 10.1118/1.594751
Abstrakt: Causes for the discrepancy noted by Grant et al. between the in-water and in-air calibration of 60Co are discussed. Data are presented from measurements with a set of ionization chambers with thimbles of 0.5, 1.0, and 1.5 cm outside radii. These data include measurements of percentage depth dose, backscatter factors, and displacement factors. The results show that the discrepancy noted by Grant et al. is caused by a combination of small errors both in depth dose data and in the displacement factor incorporated into C lambda.
Databáze: MEDLINE