This thesis concerns the use of nuclear reactions to study the structure of neutron-rich light nuclei. Emphasis is placed on 11Be which has been identified as a nucleus with a single neutron halo and which offers a simple 2-body case for detailed analysis. Comparisons are made with experimental data for the break-up of 11Be on gold, titanium and beryllium targets. As a prelude to more detailed work a simple elastic break-up model calculation, using the Distorted Wave Born Approximation (DWBA), is attempted. The resulting theoretical cross-sections show good agreement with the shape of the experimental data but cannot predict the absolute magnitude. A major part of the break-up work is a more accurate model using the post-form DWBA. The formulation is built up from basic scattering theory and includes details of employing the Zero Range Approximation and the Vincent and Fortune method of integration. A Finite Range Correction is also applied. Cross-section calculations for a gold target agree closely with experiment but a problem arises for lighter targets. Here the Coulomb potential must be excluded from the calculation to obtain a result that matches the experimental data. A method for the calculation of inelastic break-up is presented which only requires a small modification to the methods used for elastic break-up. As it suffers from the same light target problem only calculations for a gold target give an inclusive cross-section, produced from the elastic and inelastic contributions, which matches the experimental data satisfactorily. To overcome the light target problem a full recoil calculation is introduced. Arguments and analysis are produced to show that this method is too demanding of both computing time and storage for practicable implementation. Future calculations are proposed using an analytical method for Coulomb break-up.
| Identifer | oai:union.ndltd.org:bl.uk/oai:ethos.bl.uk:308413 |
| Date | January 1995 |
| Creators | Cross, Brian |
| Publisher | University of Surrey |
| Source Sets | Ethos UK |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
| Source | http://epubs.surrey.ac.uk/843872/ |
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