Use this URL to cite or link to this record in EThOS: http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.637862
Title: High-resolution translational energy loss spectrometry of single-electron capture reactions
Author: Leather, C.
Awarding Body: University of Wales Swansea
Current Institution: Swansea University
Date of Award: 1998
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Abstract:
High resolution translational energy loss single-electron capture spectra have been obtained for B2+, C2+ and N3+ in collision with H2, N2, O2, CO and NO molecular targets and He, Ne, Ar, Kr and Xe atomic targets for a range (2 - 8 keV) of collision energies, with a total of 134 reaction channels identified. Splitting of the upper [2P1/20] and lower [2P3/20] J states of Kr+ and Xe+ targets was observed, with a novel statistical method for the calculation of the J state populations being employed to find the gradient and centre of the reaction window for these systems. Experimentally determined total and partial collision cross sections have been calculated for the N3+ collision systems using a specially designed energy loss spectrometer with a wide angle of acceptance. When compared to various theoretically determined total cross sections the extended classical overbarrier model was found to be closest to the observed results, other models failing to take into account the large number of electron core violating reaction channels. The C2+ collision system was found to consist of two distinct reaction windows, separated by the nature of the entrance channel. A semi-empirical model has been postulated to account for this observation. The contribution from a specific reaction channel to a single electron capture spectrum was found to be dependent upon spin conservation, position within the reaction window and electron core conservation. The contribution by collisional broadening to the ultimate resolving power attainable by a sector instrument has been studied by the use of a short path length collision cell. By precisely registering the cell on the instrumental focal plane it was found that collisional broadening could be essentially eliminated, the major resolution-limiting component at this level being thermal broadening. A theoretical model for collisional broadening has also been developed.
Supervisor: Not available Sponsor: Not available
Qualification Name: Thesis (Ph.D.) Qualification Level: Doctoral
EThOS ID: uk.bl.ethos.637862  DOI: Not available
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