Investigating the structure of neutron rich calcium isotopes

Abstract

The behavior of neutron and proton rich nuclei that lie far from the region of stability is a matter of great scientific interest. This is because not only do these nuclei play important roles in stellar nucleosynthesis events such as the r-process, but they also allow us to observe changes in the nuclear shell structure, which helps shape our understanding of the nuclear interaction. This behavior is often attributable to the existence of shell closures, that occur at a few specific numbers of protons and neutrons. Forming a complete understanding of such shell closures requires knowledge regarding the orbital occupancies of these nuclei. Through an experiment conducted at TRIUMF, Canada’s particle accelerator center, the orbital occupancies of neutron rich Calcium isotopes have been probed. These nuclei, with a conventional closed proton shell of Z = 20, draw interest with new neutron shells signaled at N=32 and 34. An overview of the experimental process and subsequent analysis will be detailed throughout the following discussion. The overview of the experiment will detail the conditions and methods used, while the discussion of the analysis will review the steps undertaken towards the construction of ⁵⁰Ca(d,d)⁵⁰Ca Q-Value spectra.