The Integral Line-Beam Method for Gamma Skyshine Analysis

A refinement of a simplified method, based on line-beam response functions, is presented for performing skyshine calculations for shielded and collimated gamma-ray sources. New coefficients for an empirical fit to the line-beam response function are provided and a prescription for making the response function continuous in energy and emission direction is introduced. For a shielded source, exponential attenuation and a buildup factor correction for scattered photons in the shield are used. Results of the new integral line-beam method of calculation are compared to a variety of benchmark experimental data and calculations and are found to give generally excellent agreement at a small fraction of the computational expense required by other skyshine methods.