Representation of non-local optical potentials for nuclear reactions

Sammanfattning

A scattering process is the event where particles collide with each other and then move away from each other, in any direction. This is the foundation of any reaction between nuclei and is a central part of nuclear physics. In modelling these reactions, it is central to determine an effective potential, representing the reaction, to use in analysis. This potential is a complex potential referred to as an optical potential. There are two main approaches in determining it, the phenomenological and microscopic approach. The phenomenological approach fits experimental data to a model to determine the optical potential while the microscopic model instead calculates it from microscopic nuclear structure and reactions. The latter is an essential for nuclei with insufficient experimental data available. It is however difficult to construct microscopic models that have the performance of phenomenological ones. The microscopic models are numerical, making them harder to give some intuitive interpretation of nuclear reactions. This thesis takes a step towards bridging the gap between phenomenological model potentials and microscopic model potentials. Through comparative analysis, various models are projected onto one another, revealing the general shape of the microscopic model. It is then represented in an analytical form by developing an approximation of a basis for the L 2 Hilbert space that the microscopic model potential spans and then projecting the potential onto components of this basis. The result obtained from this is the general shape of the microscopic model potential investigated. It is found to be represented by a linear combination of the Wood-Saxon and Gaussian distributions and their derivatives.