Memorandum from Raymond L. Murray to Dr. Clifford K. Beck
3 pp.
August 30, 1951


August 30, 1951

TO: Clifford K. Beck
FROM: Raymond L. Murray
SUBJECT: Disturbance of neutron flux in reactor by a control rod
CC: A. C. Menius, Jr., Arthur W. Waltner, and Newton Underwood

The question was raised in a recent meeting on the amount of depression of
flux produced by a control rod in a reactor. In this note, calculations of flux
distributions for a simple reactor rod geometry are reviewed.

[page 2]

Since the method of calculation involves two separate reactors, with only a
common active solution, there is no preferable mode of normalization for compari-
. In order to illustrate the rod effect, a simple Bessel function and the
distribution with a rod are plotted in the attached graph so that the ordinates
agree near the walls. The flux is affected strongly for about a third of the way