2. A Model of Neutron Scattering We will model the case of nuclear scattering as scattering off a hard sphere of radius $R$. (a) The radius $R$ of a nucleus can be expressed as $$R = r_0A^{1/3}$$ where $R_0 = 1.1 imes 10^{-15}$ m and $A$ is the mass number of the nucleus. Suppose a neutron scatters from a Gold nucleus. For what range of neutron momenta would you expect s-wave scattering to dominate? (b) Suppose our nucleus has a kinetic energy of 1 MeV/c. What is the scattering cross section is you assume only s-wave scattering is important? (c) What is the size of the p-wave ($l = 1$) term relative to ths s-wave term calculated above?
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The wavelength of a neutron can be expressed as λ = h/p, where h is Planck's constant and p is the momentum of the neutron. The size of the nucleus is given by R = roA1/3. Show more…
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