| Title: |
Direct Evidence for the νd_{5/2} Orbital in ^{69}Ni: Implications for the N=40 Island of Inversion |
| Authors: |
Ceulemans, A.; Raabe, R.; Nowacki, F.; Alharbi, A.; Ayatollahzadeh, H.; Bennett, S. A.; Browne, F.; Butler, P. A.; Camaiani, A.; Clarke, D.; Dolan, A. J.; Eleme, Z.; Everett, C. T. A.; Flavigny, F.; Fracassetti, S.; Freeman, S. J.; Gaffney, L. P.; Georgiev, G.; Goula, S.; Heinz, A.; Kawȩcka, A.; Keatings, J. M.; Labiche, M.; Lazarus, I.; MacGregor, P. T.; Managlia, M. V.; Ojala, J.; Olaizola, Bruno; Page, R. D.; Patronis, N.; Poleshchuk, O.; Sánchez-Benítez, A. M.; Sharp, D. K.; Törnqvist, H.; Youssef, A. |
| Contributors: |
European Commission; Research Foundation - Flanders; KU Leuven; Science and Technology Facilities Council (UK); Knut and Alice Wallenberg Foundation; Ceulemans, A.; Raabe, R.; Nowacki, F.; #NODATA#; Ayatollahzadeh, H.; Camaiani, A.; Everett, C. T. A.; Flavigny, F.; Gaffney, L. P.; Georgiev, G.; Heinz, A.; Keatings, J. M.; MacGregor, P. T.; Managlia, M. V.; Olaizola, Bruno; Page, R. D. |
| Publisher Information: |
American Physical Society |
| Publication Year: |
2025 |
| Collection: |
Digital.CSIC (Consejo Superior de Investigaciones Científicas / Spanish National Research Council) |
| Subject Terms: |
physics |
| Description: |
8 pages, 5 figures, 2 tables ; Shape coexistence, a collective manifestation of nuclear structure, emerges from the underlying single-particle dynamics and is prominently observed in the region below ^{68}Ni. Theoretical studies have emphasized the key role of the νd_{5/2} orbital, the quadrupole partner of νg_{9/2}, in driving deformation. However, experimental constraints on the location and properties of neutron orbitals in neutron-rich isotopes in this region remain scarce. In this Letter, the single-particle structure of ^{69}Ni was investigated via the ^{68}Ni(d,p) reaction in inverse kinematics, performed at the ISOLDE Solenoidal Spectrometer at CERN. Several new excited states were observed, and comparisons with adiabatic distorted wave approximation (ADWA) calculations enabled ℓ-value assignments for the most strongly populated states. In particular, a state at 2.56 MeV is interpreted as the dominant fragment of the νd_{5/2} strength. The experimental findings are well reproduced by Large-Scale Shell Model calculations using a modified LNPS interaction with an increased νg_{9/2}-νd_{5/2} energy gap. These results provide new insight into the structure of ^{69}Ni and underscore the crucial role of the νd_{5/2} orbital in the onset of collectivity at the N=40 island of inversion. ; This project has received funding from the European Union’s Horizon Europe Research and Innovation programme under Grant Agreement No. 101057511, from the Research Foundation–Flanders under Projects No. I002619N, No. I002919N, and No. I012420N of the International Research Infrastructure program, from the KU Leuven internal funds under Project No. C14/22/104, and from the Science and Technology Facilities Council (UK) Grants No. ST/M00161X/1, No. ST/N002563/1, No. ST/P004598/1, No. ST/V001027/1, No. ST/Y000323/1, No. ST/Y000382/1, and No. ST/Y000242/1. A .H., A. K., M. V. M., and H. T. are grateful for funding from the Knut and Alice Wallenberg Foundation under No. KAW 2020.0076. This work was supported in part by the UK ... |
| Document Type: |
article in journal/newspaper |
| Language: |
English |
| ISSN: |
41557298 |
| Relation: |
#PLACEHOLDER_PARENT_METADATA_VALUE#; info:eu-repo/grantAgreement/EC/HE/101057511; https://doi.org/10.1103/tdfs-5qzw; Sí; Physical Review Letters 135: 252502 (2025); https://hdl.handle.net/10261/417503; https://api.elsevier.com/content/abstract/scopus_id/105025590515 |
| DOI: |
10.1103/tdfs-5qzw |
| Availability: |
https://hdl.handle.net/10261/417503; https://doi.org/10.1103/tdfs-5qzw; https://api.elsevier.com/content/abstract/scopus_id/105025590515 |
| Rights: |
info:eu-repo/semantics/openAccess |
| Accession Number: |
edsbas.779C7C90 |
| Database: |
BASE |