Depth dose determinations

For pt. I see abstr. A13171 of 1973. A complete analogue Monte Carlo program is described for the detailed computation of neutron-photon interactions with matter to at least 15 MeV, with versions for the CDC 3600 and IBM 360/75 systems. Forty-five regions, of any composition chosen from fifteen elements, may be specified, of any size, interrelation and shape expressible as algebraic functions. Similarly, a variety of sources may be included. Two geometric descriptions of Standard Man are proposed, closely matching ICRP specifications. One is an eleven region phantom which is homogeneous in composition excepting the lung regions and the second a heterogeneous phantom of 29 regions. The fraction of gamma -ray energy absorbed by, and the fraction of first collisions within these phantoms were obtained as a function of point source location along the phantom midline at gamma -ray source energies of 0.34, 2.75 and 8.00 MeV. The results obtained differ markedly, in many regions, from those previously obtained with the simple, symmetric, homogeneous solids used as human phantoms.