integral exposure rate spectra, and exposure rate angular
distributions heretofore not available.
In addition, we discuss
sensitivity of the data to source energy, source depth
distribution in the soil,
and detector height above the
interface.
The calculations were carried out using a
combination of the P-3 and DP-1 polynomial expansion matrix
equation method for solving the two media transport problem??,
Comparison of these results with those obtained using the
infinite medium moments method based on buildup factors
indicated that the latter method was probably fairly accurate
(410%)
for detector positions close to the
interface but may
have been significantly in error far from the interface,
especially for low energy sources distributed in the soil a).
In addition to the specific calculations of the differ-
ential energy spectra, integral exposure rate spectra, and
exposure rate angular distributions, the effects of varying
the soil composition, moisture content, and density are
considered together with an evaluation of the calculational
accuracy,