The Enge Split-Pole Spectrograph at the University of Notre Dame

¹ Department of Physics and Astronomy, University of Notre Dame, Notre Dame, Indiana 46556, USA
² Instituto de Física, Universidade de São Paulo, Rua do Matão 1371, São Paulo, SP 05508-090, Brazil

^* e-mail: scarmic1@nd.edu
^** e-mail: pomalle4@nd.edu

Published online: 8 October 2024

Abstract

Nuclear reactions play a crucial role in determining the nucleosynthesis that occurs in astrophysical events. The rates of many reactions that significantly impact certain nucleosynthesis processes can not be currently measured via direct means. These reactions must be constrained in another manner, such as determining the level energies and other structure properties of the compound nuclei. In order to measure level energies of nuclei relevant to nuclear astrophysics, the Enge split-pole spectrograph has been installed and commissioned at the University of Notre Dame’s Nuclear Science Laboratory. The first scientific measurement has also been performed. Structure properties of ⁵⁸Cu were measured via the reaction ⁵⁸Ni(³He,t)⁵⁸Cu to provide the first experimental constraint of the ⁵⁷Ni(p,γ)⁵⁸Cu reaction rate, which impacts the production of of ⁴⁴Ti, ⁵⁷Fe, and ⁵⁹Ni in core-collapse supernovae. Preliminary analysis of this measurement confirms the level energies of states in ⁵⁸Cu that could lead to significant resonances in the ⁵⁷Ni(p,γ)⁵⁸Cu reaction rate, while suggesting the presence of additional states that have not been previously observed but could also lead to significant resonances.