ORNL-1771 - Oak Ridge National Laboratory

PERIOD ENDING SEPTEMBER IO, 7954
Alternatively, if a single-scatter approach with attenuation by a emov oval" mechanism is used, the fol-
lowing formula is obtained:
where
X5 - scattering cross section,
C = removal cross section.
A detailed report on this calculation is being
prepared. * FOCUSING OF RADIATION IN A
CYLlNDRlCAL CREW COMPARTMENT
J. E. Faulkner
A study of the focusing of radiation in a cylindri-
cal crew compartment has been made, with particular
attention being given to the case with the following
conditions :
1. The cylinder is infinite.
2. The surface radiation density is constant
along the inner cylinder walls.
3. The angular distribution of the radiation
depends only on the angle between the direction of
emergence and the normal to the cylinder.
4. The attenuation inside the crew space is pure
inverse square.
5. The detector is isotropic.
Under these conditions the angular distribution
may be represented as an isotropic component plus
a series in odd powers of the cosine. The contri-
bution of each term at a given point in the com-
ponent in the series may be expressed in an even
polynomial in x (see Fig. 11.3), where x is the
distance of the given point from the axis.of the
cylinder divided by the radius of the cylinder.
For pure cosine distribution the reading of an
isotropic detector is independent of position in the
crew compartment.
'A. Simon and H. E. Stern, Some Cuiculutionul Methods
jor Air md Ground Scattering, ORNL CF-54-8-103 (to be
i s sued).
s
3
t
1 .o
0.8
0.6
v7
6 0.4
b-
I
0.2
0
0
1 CROSS SECTION OF
CREW COMPARTMENT
x=h/R
......
ylr
ORNL-LR-DWG 2647
STERADIAN IN ThE NORMOL DIRECTION
0.2 0.4
X
0.6 0.8 i.0
Fig. 11.3. Variation of Radiation Intensity with
Distance from Center of Crew Compartment.
163