First nuclear reaction measurement using the CARME array

Abstract

The broad outline of nucleosynthesis is well established; however, our understanding of it is not yet complete. In many cases, advances in astronomical observations have placed the burden of further understanding on an improved understanding of key nuclear physics processes. High precision nuclear physics measurements are required to reduce the uncertainty of these processes which significantly influence a range of astrophysical scenarios. These measurements can be extremely challenging to perform using current methodologies and require new experimental techniques. Storage rings provide one such methodology by performing nuclear reaction studies using stored heavy ion beams on an ultra-thin internal gas-jet target. My PhD project is devoted the installation and commissioning of the CRYRING Array for Reaction Measurements (CARME), which utilises this novel methodology and will aim to address many of the outstanding problems requiring improved nuclear physics inputs.

In this thesis the methodology of using storage rings for nuclear reaction studies is presented in addition to details of the CARME array and its commissioning. The commissioning process includes the extensive vacuum commissioning required for storage ring operations, in addition to the data analysis procedures developed to determine nuclear parameters from an experiment. The first experimental run using the CARME array used a deuteron beam on a nitrogen target at beam energies of 1.5 and 5.5 MeV/u. Several states from the 14N(d, p)15N and 14N(d, α)12C reactions were identified, and the cross sections of these states have been compared to previous measurements. DWBA calculations have been performed to model the angular distribution of the 14N(d, p5)15N reaction, and the spectroscopic factor has been extracted. This spectroscopic factor is in agreement with the spectroscopic factors reported in previous experimental measurements and theoretical calculations.