Unit 9 : Additional Problems

For those looking for additional problems outside of past exam questions and the worked problems in the lectures please consider the following in the reading list.

Unworked Problem : Neutron Sources

The two common laboratory-scale (as opposed to national facility scale) neutron sources are AmBe (as discussed in the example) and d-t fusion generators. Compare and contrast these two source types.

Unworked Problem : Reactor Spectra

There are two “reactor neutron” energy spectra shown in the lecture, one (from the IPEN/MB01 research reactor) on slide 7 and one (comparing reactor and spallation neutrons) on slide 8. They do not look the same. Both come from reputable sources, so we can reasonably assume that both are in some sense “right”. What do you think causes the difference?

Unworked Problem : 14 MeV Neutrons

Verify the statement in the notes that the energy of the neutrons emitted in the \( ^{3}H(d,n)^{4}He \) reaction is 14 MeV, stating any assumptions that you make.

Unworked Problem : Alternative Yield

Repeat the above calculation for (i) \( ^{1}H \), (ii) \( ^{2}H \), and (iii) \( ^{238}U \), and comment on your results.

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Unworked Problem : Excited States

In thermal neutron capture by \( ^{55}Mn \), the following \( \gamma \)-ray energies (in MeV) are observed: 7.2703, 7.2438, 7.1597, 7.0578, 6.9287. Deduce the energies of the corresponding \( ^{56}Mn \) excited states.

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Unworked Problem : He3 Detectors

Helium-3 gas proportional chambers are widely used as thermal neutron detectors. The reaction is \( ^{3}He(n,p)^{3}H \). What is the Q-value of this reaction? Estimate the energy of the produced proton, stating any assumptions that you make.