Exploring the low-Z shore of the island of inversion at n=19

G Christian; N Frank; S Ash; T Baumann; D Bazin; J Brown; P A DeYoung; J E Finck; A Gade; G F Grinyer; A Grovom; J D Hinnefeld; E M Lunderberg; B Luther; M Mosby; S Mosby; T Nagi; G F Peaslee; W F Rogers; J K Smith; J Snyder; A Spyrou; M J Strongman; M Thoennessen; M Warren; D Weisshaar; A Wersal

doi:10.1103/PhysRevLett.108.032501

Exploring the low-Z shore of the island of inversion at n=19

Phys Rev Lett. 2012 Jan 20;108(3):032501. doi: 10.1103/PhysRevLett.108.032501. Epub 2012 Jan 19.

Authors

Affiliation

¹ Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48824, USA. chris402@msu.edu

PMID: 22400733
DOI: 10.1103/PhysRevLett.108.032501

Abstract

The technique of invariant mass spectroscopy has been used to measure, for the first time, the ground state energy of neutron-unbound (28)F, determined to be a resonance in the (27)F+n continuum at 220(50) keV. States in (28)F were populated by the reactions of a 62 MeV/u (29)Ne beam impinging on a 288 mg/cm(2) beryllium target. The measured (28)F ground state energy is in good agreement with USDA/USDB shell model predictions, indicating that pf shell intruder configurations play only a small role in the ground state structure of (28)F and establishing a low-Z boundary of the island of inversion for N=19 isotones.