Understanding Neutron Scattering from Nuclei: Questions and Answers

ryanwilk
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Homework Statement



I have a (numerically calculated) cross section for a neutron scattering from a nucleus which looks like:

SW-U-50l9.png


1) Am I correct in saying that there are three resonant peaks and these correspond to three different resonant particles?

2) If so, are the lifetimes of the particles just h-bar divided by the width?

3) Why is this cross section more complicated than neutron scattering from lower mass nuclei?

4) I was unable to find any experimental values for these resonances. Is this because I'm looking at energies in MeV, which is difficult to do experimentally?

5) Other than peak positions, decay widths and cross sections, can anything else be determined from this graph?

Homework Equations



The total scattering cross section is:

\sigma = \frac{4 \pi}{k^2} \sum_{l=0}^{\infty} (2l+1) ~\mathrm{sin}^2 \delta_l\>..

The Attempt at a Solution



(Given in 1)

Answers to any of the questions would be greatly appreciated!

Thank you.
 
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