Question

1. A collimated beam of 1.5 MeV gamma rays strikes a thin tantalum foil. Electrons of 0.7 MeV energy are observed to emerge from the foil. Are these due to the photoelectric effect, Compton scattering or pair production? Assume that any electrons produced in the initial interaction with the material of the tantalum foil do not undergo a second interaction. 2. Compare the energy loss of a photon in the following situations. (a) One single Compton scattering through 180 (b) Two successive scatterings through 90° each (c) Three successive scatterings through 60 each

Answer 1

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