A collective coupled-channel model and mirror state energy displacements

• Published in: The European physical journal. A, Hadrons and nuclei Vol. 51; no. 9
• Main Authors: Fraser, P. R., Amos, K., Canton, L., Karataglidis, S., van der Knijff, D., Svenne, J. P.
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 14.09.2015
• Subjects: Hadrons; Heavy Ions; Nuclear Fusion; Nuclear Physics; Particle and Nuclear Physics; Physics; Physics and Astronomy; Regular Article - Theoretical Physics; Charge Distribution; Nuclear Interaction; Mirror Pair; Ground State Energy; Pauli Blocking
• ISSN: 1434-6001; 1434-601X
• DOI: 10.1140/epja/i2015-15110-4

The spectra of nucleon-nucleus mirror systems allow examination of charge symmetry breaking in nucleon-nucleus interactions. To date, such examination has been performed with studies using microscopic models of structure. Herein we seek characterisation with a coupled-channel model in which the nucleon-nucleus interactions are described using a collective model prescription with the Pauli principle taken into account. The neutron-nucleus Hamiltonian is chosen to give the best match to the compound system spectrum, with emphasis on finding the correct ground state energy relative to the neutron-nucleus threshold. The Coulomb interactions for the proton-nucleus partner of a mirror pair are determined using charge distributions that match the root-mean-square charge radii of the nuclei in question. With the Coulomb interaction so defined modifying the neutron-nucleus Hamiltonian, we then predict a spectrum for the relevant proton-nucleus compound. Discrepancies in that resulting spectrum with measured values we tentatively ascribe to charge-symmetry breaking effects. We consider spectra obtained in this way for the mirror pairs 13 C and 13 N, 15 C and 15 F, and 15 O and 15 N, all to ∼ 10 MeV excitation.