Calculations have been carried out in the distorted-wave Born approximation for electron-impact excitation of the individual 2p fine-structure states of the hydrogen atom. Results are given for 54.4, 100, and 200 eV. The purpose was not to improve on existing more elaborate calculations of the state multipoles of the excited 2p states, but rather to investigate spin-related phenomena, such as an incident polarized beam, polarized target atoms, and the polarization of the scattered electrons when unpolarized electrons are incident on unpolarized target atoms. The bound state wave functions are constructed using the total angular momentum scheme, $\vert JM\sb{J}\rangle = \sum\limits\sb{M\sb{L}M\sb{S}}C(LSJ;M\sb{L}M\sb{S}M\sb{J})\vert LM\sb{L}SM\sb{S}\rangle$, and the Percival-Seaton hypothesis is not used. We then construct explicitly-spin-dependent scattering amplitudes. This approach is to be contrasted with previous calculations which use $\vert LM\sb{L}SM\sb{S}\rangle$ wave functions and assume that the sum of the electron spin projections is conserved in the collision, or with calculations which use uncoupled wave functions. / The spin polarization of the scattered electrons resulting from scattering unpolarized electrons on unpolarized ground state hydrogen atoms (the 'fine-structure effect') is found to result here from interference of the direct and exchange scattering amplitudes. Distortion of the scattered waves by the atomic potential produces a nonzero component of the transferred angular momentum perpendicular to the scattering plane. This orbital angular momentum orientation of the excited atom is then transferred to the scattered electron via angular momentum algebra. The spin-orbit interaction in the excited atom is the origin of the spin polarization, since it produces a sufficient energy separation of the fine structure states to allow them to be studied separately. / Source: Dissertation Abstracts International, Volume: 56-04, Section: B, page: 2085. / Major Professor: W. N. Shelton. / Thesis (Ph.D.)--The Florida State University, 1995.
| Identifer | oai:union.ndltd.org:fsu.edu/oai:fsu.digital.flvc.org:fsu_77451 |
| Contributors | Jain, Babu Lal., Florida State University |
| Source Sets | Florida State University |
| Language | English |
| Detected Language | English |
| Type | Text |
| Format | 189 p. |
| Rights | On campus use only. |
| Relation | Dissertation Abstracts International |
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