Inelastic scattering of heavy ions to low-lying collective states is studied. Symmetries of the scattering amplitude are discussed and, in particular, the conditions for the validity of an approximate symmetry property are derived. One condition is that the excitation should be 'adiabatic'. The consequences of this approximate symmetry are given: these include zero vector polarization and a gamma-ray distribution that is symmetric about the direction of recoil. In the more general case, and under strong absorption conditions, the full inelastic scattering amplitude is decomposed into components corresponding to waves turning in opposite directions about the scattering centre. It is shown that this allows a simple interpretation of cross-section structure, particularly in the quasi-classical limit, which is derived and explained. The polarization and γ-ray symmetry angle are also discussed in these terms, and conditions of weaker absorption and Coulomb excitation are considered using the same method. A new proof of the asymptotic form of certain Clebsch-Gordan coefficients is given, and a useful property of spherical harmonics derived.
| Identifer | oai:union.ndltd.org:bl.uk/oai:ethos.bl.uk:331099 |
| Date | January 1982 |
| Creators | Dean, David Robert |
| Publisher | University of Oxford |
| Source Sets | Ethos UK |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
| Source | https://ora.ox.ac.uk/objects/uuid:992a3988-4a25-4b23-b9c4-07698ebd8697 |
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