[Dosimetric studies of 192Ir line sources and the mathematical presentation of the dose distribution].

Abstract

The dose distribution of a "line-shaped" 192Ir-source was measured in 1,152 measuring points in a water phantom. Using regression analysis the analytical description of dose distribution was obtained. Accomplished comparison measurings with a solid phantom of miramide in 45 measuring points show that the dose distribution can be reproduced well by solid phantom measurings. Taking an ideal line source distribution as a basis, the r-dependence of correction factor, obtained by regression analysis, refers to a dispersion effect. The angle-dependent deviation of dose distribution from the ideal line source can be described by cos-terms with the single and double angle between line source axis and measuring point.