|dc.description.abstract||A knowledge of the spectral distribution of scattered
radiation at a point is of value in planning effective radiation
therapy and adequate personnel protection. Some spectra have been
calculated theoretically or measured experimentally for a few
particular irradiation conditions.
In this investigation, the spectral distributions of multiply-scattered
Co60 radiation were measured at depths of 2 cm., 5 cm.,
10 cm. and 15 cm. in tissue-equivalent material with beam areas of
25 cm.2 and 100 cm.2. Total-scatter spectra, including both singly- and
multiply-scattered radiation, were measured at various angles.
Then, upon subtraction of the single-scatter spectra contribution
from the total-scatter spectra, multiple-scatter spectra were obtained.
The integrated and corrected multiple-scatter spectra were compared
to corresponding spectra derived from data calculated by Bruce using
the Monte Carlo method.
The shapes of the experimental multiple-scatter spectra show
fair agreement with Bruce's theoretical spectra. The greatest discrepancy
between the spectra occurs in the low-energy end of the spectra.
For all measured depths and beam areas the theoretical low-energy peaks
appear at an energy from 10 to 30 KeV higher than that of the experimental