- Physical Review Journals
All JournalsPhysics Magazine

Physical Review Letters

Reuse & Permissions

It is not necessary to obtain permission to reuse this article or its components as it is available under the terms of the Creative Commons Attribution 4.0 International license. This license permits unrestricted use, distribution, and reproduction in any medium, provided attribution to the author(s) and the published article's title, journal citation, and DOI are maintained. Please note that some figures may have been included with permission from other third parties. It is your responsibility to obtain the proper permission from the rights holder directly for these figures.

Export citation

Export citation

Choose format for download:

Download Citation
  • Open Access

Collapse of Nuclear Collectivity along the N=Z Line

M. A. Bentley1,*, R. Taniuchi1, R. Wadsworth1, H. Iwasaki2,3, D. D. Dao4, F. Nowacki4, M. J. Basson2,3, T. Beck2,†, B. Cederwall5 et al.

J. Chen2,3, S. Chen1, J. Dobaczewski1,6, M. Doncel7, A. Douglas2,3, P. Farris2,3, A. Gade2,3, S. A. Gillespie2, A. M. Hill2,3, D. G. Jenkins2,1, J. Chung-Jung2,3, S. M. Lenzi8, W. Marshall1, S. Paschalis1, J. Pereira2, X. Pereira-Lopez9, M. Petri1, R. Salinas2,3, A. Sanchez2,3, J. A. Swartz2, C. Tinson2,3, D. Weisshaar2, and K. Wimmer10

  • *Contact author: michael.bentley@york.ac.uk
  • †Present address: KU Leuven, Instituut voor Kern- en Stralingsfysica, Celestijnenlaan 200d, 3001 Leuven, Belgium.
PDF

Phys. Rev. Lett. 136, 152501 – Published 17 April, 2026

DOI: https://doi.org/10.1103/r6ns-ypw8

Abstract

The lifetime of the Jπ=2+ state in the self-conjugate Ru88 nucleus has been determined in an experiment performed using rare-isotope beams provided by the new Facility for Rare Isotope Beams. This is the heaviest N=Z nucleus for which such a measurement has been achieved. Ru88 was populated by both one-neutron knockout and charge-exchange reactions, and the lifetime of 14.3−3.4+2.5  ps was determined using the triple-foil plunger technique. The extracted electromagnetic transition strength shows that the quadrupole collectivity has dropped significantly compared with the highly deformed N=Z region around A∼80. These results are compared with state-of-the-art large-scale shell-model and discrete nonorthogonal shell-model calculations. The theoretical calculations indicate a moderate triaxial deformation and suggest that low-lying states in this nucleus are no longer dominated by strong many-particle many-hole excitations, unlike the lighter, highly deformed N=Z nuclei nearby.

View figure in article

Physics Subject Headings (PhySH)

Article Text

Supplemental Material

References (46)

  1. A. Lemasson, H. Iwasaki, C. Morse, D. Bazin, T. Baugher, J. S. Berryman, A. Dewald, C. Fransen, A. Gade, S. McDaniel, A. Nichols, A. Ratkiewicz, S. Stroberg, P. Voss, R. Wadsworth, D. Weisshaar, K. Wimmer, and R. Winkler, Phys. Rev. C 85, 041303(R) (2012).
  2. R. D. O. Llewellyn et al., Phys. Rev. Lett. 124, 152501 (2020).
  3. P. Federman and S. Pittel, Phys. Rev. C 20, 820 (1979).
  4. K. Kaneko, N. Shimizu, T. Mizusaki, and Y. Sun, Phys. Lett. B 817, 136286 (2021).
  5. A. P. Zuker, A. Poves, F. Nowacki, and S. M. Lenzi, Phys. Rev. C 92, 024320 (2015).
  6. D. D. Dao and F. Nowacki, Phys. Rev. C 105, 054314 (2022).
  7. D. D. Dao and F. Nowacki, arXiv:2507.09073.
  8. D. D. Dao and F. Nowacki, arXiv:2409.08210.
  9. J. Ha, F. Recchia et al., Nat. Commun. 16, 10631 (2025).
  10. T. Glasmacher, A. Gade, G. Bollen, and J. Wei, Nucl. Phys. News 34, 5 (2024).
  11. See Supplemental Material at http://link.aps.org/supplemental/10.1103/r6ns-ypw8 for further details of the experiment, simulation, data analysis, and theoretical models, which includes Refs. [12–15].
  12. E. Caurier and F. Nowacki, Acta Phys. Pol. B 30, 705 (1999), https://www.actaphys.uj.edu.pl/R/30/3/705/pdf.
  13. K. W. Schmid, F. Grümmer, and A. Faessler, Phys. Rev. C 29, 308 (1984).
  14. K. W. Schmid, F. Grümmer, and A. Faessler, Phys. Rev. C 29, 291 (1984).
  15. K. Schmid, Prog. Part. Nucl. Phys. 52, 565 (2004).
  16. M. Hausmann, A. Aaron, A. Amthor, M. Avilov, L. Bandura, R. Bennett, G. Bollen, T. Borden, T. Burgess, S. Chouhan, V. Graves, W. Mittig, D. Morrissey, F. Pellemoine, M. Portillo, R. Ronningen, M. Schein, B. Sherrill, and A. Zeller, Nucl. Instrum. Methods Phys. Res., Sect. B 317, 349 (2013).
  17. H. Iwasaki, A. Dewald, T. Braunroth, C. Fransen, D. Smalley, A. Lemasson, C. Morse, K. Whitmore, and C. Loelius, Nucl. Instrum. Methods Phys. Res., Sect. A 806, 123 (2016).
  18. D. Bazin, J. Caggiano, B. Sherrill, J. Yurkon, and A. Zeller, Nucl. Instrum. Methods Phys. Res., Sect. B 204, 629 (2003).
  19. S. Paschalis et al., Nucl. Instrum. Methods Phys. Res., Sect. A 709, 44 (2013).
  20. D. Weisshaar et al., Nucl. Instrum. Methods Phys. Res., Sect. A 847, 187 (2017).
  21. K. Wimmer, GrROOT, https://github.com/wimmer-k/GrROOT (2012–2015).
  22. B. Cederwall et al., Phys. Rev. Lett. 124, 062501 (2020).
  23. D. Abriola, M. Bostan, S. Erturk, M. Fadil, M. Galan, S. Juutinen, T. Kibédi, F. Kondev, A. Luca, A. Negret, N. Nica, B. Pfeiffer, B. Singh, A. Sonzogni, J. Timar, J. Tuli, T. Venkova, and K. Zuber, Nucl. Data Sheets 110, 2815 (2009).
  24. P. Adrich, D. Enderich, D. Miller, V. Moeller, R. Norris, K. Starosta, C. Vaman, P. Voss, and A. Dewald, Nucl. Instrum. Methods Phys. Res., Sect. A 598, 454 (2009).
  25. S. Agostinelli et al., Nucl. Instrum. Methods Phys. Res., Sect. A 506, 250 (2003).
  26. M. A. Bentley et al. (to be published).
  27. H. G. Price, C. J. Lister, B. J. Varley, W. Gelletly, and J. W. Olness, Phys. Rev. Lett. 51, 1842 (1983).
  28. R. F. Casten and N. V. Zamfir, Phys. Rev. Lett. 70, 402 (1993).
  29. J. P. Delaroche, M. Girod, J. Libert, H. Goutte, S. Hilaire, S. Péru, N. Pillet, and G. F. Bertsch, Phys. Rev. C 81, 014303 (2010).
  30. K. Starosta et al., Phys. Rev. Lett. 99, 042503 (2007).
  31. A. Obertelli, T. Baugher, D. Bazin, J. P. Delaroche, F. Flavigny, A. Gade, M. Girod, T. Glasmacher, A. Goergen, G. F. Grinyer, W. Korten, J. Ljungvall, S. McDaniel, A. Ratkiewicz, B. Sulignano, and D. Weisshaar, Phys. Rev. C 80, 031304(R) (2009).
  32. A. Nichols et al., Phys. Lett. B 733, 52 (2014).
  33. H. Iwasaki et al., Phys. Rev. Lett. 112, 142502 (2014).
  34. K. Wimmer et al., Eur. Phys. J. A 56, 159 (2020).
  35. B. Pritychenko, M. Birch, B. Singh, and M. Horoi, At. Data Nucl. Data Tables 107, 1 (2016).
  36. K. Arnswald et al., Phys. Lett. B 772, 599 (2017).
  37. P. Voss et al., Phys. Rev. C 96, 024305 (2017).
  38. S. M. Lenzi, F. Nowacki, A. Poves, and K. Sieja, Phys. Rev. C 82, 054301 (2010).
  39. D. D. Dao, F. Nowacki, and A. Poves (to be published).
  40. C. W. Johnson and C. Jiao, J. Phys. G 46, 015101 (2018).
  41. K. Sieja and F. Nowacki, Phys. Rev. C 85, 051301(R) (2012).
  42. M. Honma, T. Otsuka, T. Mizusaki, and M. Hjorth-Jensen, Phys. Rev. C 80, 064323 (2009).
  43. K. Kaneko, Y. Sun, and G. de Angelis, Nucl. Phys. A957, 144 (2017).
  44. K. Kaneko, T. Mizusaki, Y. Sun, and S. Tazaki, Phys. Rev. C 89, 011302(R) (2014).
  45. E. Caurier, G. Martínez-Pinedo, F. Nowacki, A. Poves, and A. P. Zuker, Rev. Mod. Phys. 77, 427 (2005).
  46. M. A. Bentley, University of York Research Database: 10.15124/f57f886f-3b85-46a5-845f-e31a007acfcd (2025).

Outline

Information

Phys. Rev. Lett. 136, 152501– Published 17 April, 2026
  • Received 28 November 2025
  • Revised 11 February 2026
  • Accepted 24 March 2026
Crossmark - Check for updates button
Creative Commons Logo

Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article’s title, journal citation, and DOI.

Published by the American Physical Society

Sign In to Your Journals Account

Filter

Filter

Article Lookup

Enter a citation