73
4. A material is found to have a tenththickness of 2.3 cm for 1.25MeV gamma
rays. (a) What is the linear attenuation coefficient for this material? (b) What
is the halfthickness? (c) What is the meanfreepath length for 1.25MeV
photons in this material?
Solution:
1
x= =
0.999 cw.
IL
5. In natural uranium, 0.720% of the atoms are the isotope 235U, 0.0055% are
234U,and the remainder 238U. From the data in Table C.I, what is the total
linear interaction coefficient (macroscopic cross section) for a thermal neutron
in natural uranium? What is the total macroscopic fission cross section for
thermal neutrons?
Solution:
From the data in Table A.3, the atom density of natural uranium is
This is the end of the preview.
Sign up
to
access the rest of the document.
 Spring '06
 CADY
 Atom, Neutron, fission cross section, iL, natural uranium, macroscopic fission cross

Click to edit the document details