The passage of gamma-rays through water

Abstract

The dosage attenuation in water of γ-rays from ¹⁹⁸Au, ⁶⁰Co and ²⁴Na has been measured as a function of the source-detector distance over a range from some 3–4 to about 8–12 scattering mean free paths. The primary radiation was collimated in such a direction that none fell on the detector, down to an angle which was varied between 30° and 80°. Theoretical intensities have been calculated by an approximate procedure that replaces the direct solution of the kinetic equation by the reduction of a triple integral and are in satisfactory agreement with observation.