Single-particle and collective excitations in the N=28 isotones ⁵⁴Fe and ⁵³Mn

Summary, in English

The fusion-evaporation reaction ³²S + ²⁸Si at 125 MeV beam energy was used to populate high-spin states in the semimagic N = 28 nuclei ⁵³Mn and ⁵⁴Fe. With a combination of the Gammasphere spectrometer and ancillary devices including the Microball CsI(Tl) array, extensive high-spin level schemes are derived. They exhibit rotational-like collective structures and competing single-particle excitations. The experimental results are compared with predictions from shell-model calculations, for which the inclusion of isopin-symmetry-breaking terms is found to improve the description. An interpretation of the high-spin states is put forward using cranked Nilsson-Strutinsky calculations, indicative of contributions from collective excitations beyond some 8-MeV excitation energy and highlighting the importance of the g9/2 intruder orbital in this energy range.

• Author: D. Rudolph; I. Ragnarsson; C. Andreoiu; M. A. Bentley; M.P. Carpenter; R. J. Charity; R. M. Clark; J. Ekman; C. Fahlander; P. Fallon; W. Reviol; D. G. Sarantites; D. Seweryniak
• Department/s: Nuclear physics; Mathematical Physics
• Publishing year: 2020-07-21
• Language: English
• Publication/Series: Physical Review C
• Volume: 102
• Issue: 1
• Full text: - 922 kB; Download statistics
• Links: http://dx.doi.org/10.1103/PhysRevC.102.014316
• Document type: Journal article
• Publisher: American Physical Society
• Topic: Subatomic Physics
• Keywords: Nuclear structure; Gamma-ray spectroscopy; Shell model calculations; Rotational bands
• Status: Published
• Project: Nuclear Structure at the Limits: Isotope-selective Spectroscopy
• ISBN/ISSN/Other: ISSN: 2469-9985