Vertical distribution of the intensity of ionization due to terrestrial gamma-radiation

Formulae concerning the intensity of ionization due to the terrestrial gamma-radiations which include both the primary gamma-radiation from radioactive nuclides in the ground and the radiation scattered in soil and air were obtained by using build-up data with respect to aluminum and water for a point source. The intensities of ionization due to terrestrial gamma-radiation above and below the ground surface were calculated by the formulae with the aid of the "true" photon spectrum of the radiation in the air on the campus of Nagoya University, and the relation between the ionization intensity and altitude or depth was obtained.