In reply to David Roberson's message of Tue, 26 Mar 2013 02:39:50 -0400 (EDT): Hi, [snip] >Eric, > > >I was thinking that the neutrons would move relatively freely through matter >since they lack a charge to interact and the physical sizes of the nuclei as >well as the neutron are so small compared to the electron orbitals. How >quickly does the cross section fall as neutron energy goes up? Can you relate >them as an inverse proportion?
Look at the slope of the neutron absorption cross-section graphs at low energies. (Note that they are double logarithmic graphs.) BTW I think that these graphs are produced using semi-empirical equations, which are also provided if you hunt around a bit. Regards, Robin van Spaandonk http://rvanspaa.freehostia.com/project.html
