Analytical calculations of the solid angle subtended by a circular disk detector at linear sources

摘要

Knowledge of the geometrical solid angle is crucial in all measurements of the assets of radioactive materials and to calibrate detectors. A direct mathematical formalism for the determination of the geometrical solid angle and the geometrical efficiency of a circular disk detector and an arbitrarily positioned line source is deduced. The results have been linked with previous computational treatments. The comparison shows a very satisfactory agreement in all cases.