Calculation of geometric coefficients in nuclear radiation measurements

The geometric coefficient of radioactive sources depends on the position of the source with regard to the radiation exposed effective area of the detector as well as on the geometrical shape of the source. Assuming plane circular detector surfaces, geometric coefficients were calculated for point sources in various positions, line sources, plane disc sources as well as spherical and cylindrical sources with the aid of a computer code written in ALGOL. The results were consistent with each other. They were checked by independent procedures or measured data. The accuracy of the calculation may be chosen according to existing requirements. (author)