Electron scattering measurements of inelastic M3 transitions

MacGregor, I.J.D. , Johnson, A. and Ewing, J.S. (1984) Electron scattering measurements of inelastic M3 transitions. Nuclear Physics A, 412(1), pp. 1-12. (doi: 10.1016/0375-9474(84)90382-8)

Abstract

Inelastic M3 form factors for the excitation of the 5.236 MeV 3+ state in 24Mg and for the excitation of the 10.376 MeV 3+, T = 1 state in 28Si have been measured. These form factors are compared with full 2s1d shell-model calculations in order to investigate the experimental quenching of M3 transition strength which is expected in the light of previous work. The shell-model predictions do not agree with the experimental data. In the case of the 24Mg 5.236 MeV state the data are enhanced by a factor of ∼2 with respect to the shell-model prediction, whereas in the case of the 28Si 10.376 MeV state the data are suppressed by a factor of ∼5. In the former case it is found that a small admixture of the 32+ state shell-model wave function into the 31+ state wave function gives good agreement with the data. The effects of this admixture on other observables are investigated. No similar mechanism is found to explain the 28Si M3 transition. In view of the basic disagreement between the shell-model predictions and the experimental data, no conclusions about M3 quenching can be drawn. The validity of previous analyses using this technique is seriously questioned.

• Item Type: Articles
• Keywords: Nuclear reactions
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: MacGregor, Professor Douglas
• Authors: MacGregor, I.J.D., Johnson, A., and Ewing, J.S.
• Subjects: Q Science > QC Physics
• College/School: College of Science and Engineering > School of Physics and Astronomy
• Research Group: Nuclear Physics
• Journal Name: Nuclear Physics A
• ISSN: 0375-9474
• ISSN (Online): 1873-1554
• Copyright Holders: Elsevier BV