Extending the Southern Shore of the Island of Inversion to F-28
Journal article, 2020

Detailed spectroscopy of the neutron-unbound nucleus F-28 has been performed for the first time following proton/neutron removal from Ne-29/F-29 beams at energies around 230 MeV=nucleon. The invariant-mass spectra were reconstructed for both the F-27((*)) + n and F-26((*)) + 2n coincidences and revealed a series of well-defined resonances. A near-threshold state was observed in both reactions and is identified as the F-28 ground state, with S-n(F-28) = -199(6) keV, while analysis of the 2n decay channel allowed a considerably improved S-n(F-27) = 1620(60) keV to be deduced. Comparison with shell-model predictions and eikonal-model reaction calculations have allowed spin-parity assignments to be proposed for some of the lower-lying levels of F-28. Importantly, in the case of the ground state, the reconstructed F-27 + n momentum distribution following neutron removal from F-29 indicates that it arises mainly from the 1p(3/2) neutron intruder configuration. This demonstrates that the island of inversion around N = 20 includes F-28, and most probably F-29, and suggests that O-28 is not doubly magic.

Author

A. Revel

CEA DRF CNRS IN2P3

O. Sorlin

CEA DRF CNRS IN2P3

F. M. Marques

University of Caen Normandy

Y. Kondo

Tokyo Institute of Technology

J. Kahlbow

RIKEN

Technische Universität Darmstadt

T. Nakamura

Tokyo Institute of Technology

N. A. Orr

University of Caen Normandy

F. Nowacki

University of Strasbourg

Centre national de la recherche scientifique (CNRS)

J. A. Tostevin

University of Surrey

C. X. Yuan

Sun Yat-Sen University

N. L. Achouri

University of Caen Normandy

H. Al Falou

Lebanese American University

L. Atar

Technische Universität Darmstadt

T. Aumann

Technische Universität Darmstadt

Helmholtz

H. Baba

RIKEN

K. Boretzky

Helmholtz

C. Caesar

Helmholtz

Technische Universität Darmstadt

D. Calvet

University Paris-Saclay

H. Chae

Inst for Basic Sci Korea

N. Chiga

RIKEN

A. Corsi

University Paris-Saclay

H. L. Crawford

Lawrence Berkeley National Laboratory

F. Delaunay

University of Caen Normandy

A. Delbart

University Paris-Saclay

Q. Deshayes

University of Caen Normandy

Z. Dombradi

Inst Nucl Res

C. A. Douma

University of Groningen

Z. Elekes

Inst Nucl Res

P. Fallon

Lawrence Berkeley National Laboratory

I Gasparic

Rudjer Boskovic Inst

RIKEN

J-M Gheller

University Paris-Saclay

J. Gibelin

University of Caen Normandy

A. Gillibert

University Paris-Saclay

M. N. Harakeh

University of Groningen

Helmholtz

W. He

RIKEN

A. Hirayama

Tokyo Institute of Technology

C. R. Hoffman

Argonne National Laboratory

M. Holl

Helmholtz

A. Horvat

Helmholtz

A. Horvath

Eötvös Loránd University (ELTE)

J. W. Hwang

Seoul National University

T. Isobe

RIKEN

N. Kalantar-Nayestanaki

University of Groningen

S. Kawase

Kyushu University

S. Kim

Seoul National University

K. Kisamori

RIKEN

T. Kobayashi

Tohoku University

D. Koerper

Helmholtz

S. Koyama

University of Tokyo

I Kuti

Inst Nucl Res

V Lapoux

University Paris-Saclay

Simon Lindberg

Chalmers, Physics, Subatomic and Plasma Physics

S. Masuoka

University of Tokyo

J. Mayer

University of Cologne

K. Miki

Michigan State University

T. Murakami

Kyoto University

M. Najafi

University of Groningen

K. Nakano

Kyushu University

N. Nakatsuka

Kyoto University

Thomas Nilsson

Chalmers, Physics

A. Obertelli

University Paris-Saclay

F. de Oliveira Santos

CEA DRF CNRS IN2P3

H. Otsu

RIKEN

T. Ozaki

Tokyo Institute of Technology

V Panin

RIKEN

S. Paschalis

Technische Universität Darmstadt

D. Rossi

Technische Universität Darmstadt

A. T. Saito

Tokyo Institute of Technology

T. Saito

University of Tokyo

M. Sasano

RIKEN

H. Sato

RIKEN

Y. Satou

Seoul National University

H. Scheit

Technische Universität Darmstadt

F. Schindler

Technische Universität Darmstadt

P. Schrock

University of Tokyo

M. Shikata

Tokyo Institute of Technology

Y. Shimizu

RIKEN

H. Simon

Helmholtz

D. Sohler

Inst Nucl Res

L. Stuhl

RIKEN

S. Takeuchi

Tokyo Institute of Technology

M. Tanaka

Osaka University

M. Thoennessen

Michigan State University

H. Tornqvist

Technische Universität Darmstadt

Y. Togano

Tokyo Institute of Technology

T. Tomai

Tokyo Institute of Technology

J. Tscheuschner

Technische Universität Darmstadt

J. Tsubota

Tokyo Institute of Technology

T. Uesaka

RIKEN

Z. Yang

RIKEN

M. Yasuda

Tokyo Institute of Technology

K. Yoneda

RIKEN

Physical Review Letters

0031-9007 (ISSN) 1079-7114 (eISSN)

Vol. 124 15 152502

Subject Categories

Subatomic Physics

DOI

10.1103/PhysRevLett.124.152502

PubMed

32357034

More information

Latest update

9/15/2020