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Read the remarks on Radiation Safety (PHY293 Lab Manual, pp. 81), and and complete the Radiation Safety Questionaire and bring it with you for the Wednesday class meeting.
A hypothetical nucleus decays by emission of gamma-rays with energies 630 keV, 1.1 MeV and 3.5 MeV. When those gamma rays interact with the NaI(Tl) detector as described in the lab manual, the individual gamma-rays themselves may be fully absorbed and thus contribute to the full-energy or photopeak. However, other interactions with the detector are also possible and will give rise to additional features in the recorded spectrum, such as the Compton shoulder. Determine the energies at which you would expect the Compton shoulders for the three gamma rays given above.
For each of the gamma-rays listed above, identify what other type(s) of gamma-ray/detector interaction(s) is (are) possible, and at what energies you would look for them in the recorded spectrum. Briefly describe the physics behind each interaction.
Discuss the possibility and the likelyhood of pair-production for the 1.1 MeV gamma-ray. Which of the three interaction is the dominant one for this gamma-ray?
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