The unbound isotopes He-9,He-10
Journal article, 2010

The unbound nuclei He-9 and He-10 have been produced in proton-knockout reactions from a 280 MeV/u Li-11 beam impinging on a liquid hydrogen target at the ALADIN-LAND setup at GSI. Information on their nuclear structure has been obtained from the relative-energy spectra, He-8 + n and He-8 + 2n, employing reaction models incorporating the structure of Li-11. The (8H)e + n relative-energy spectrum is dominated by a strong peak-like structure at low energy, which may be interpreted within the effective-range approximation as the result of an s-wave interaction with a neutron scattering length of -3.17(66) fm. This spectrum also shows evidence for resonance states at 1.33(8) MeV and at 2.4 MeV above the He-8 + n threshold. It is argued that the s-state might not be the He-9 ground state. For He-8 + n + n, the analysis of the relative-energy spectrum gives two alternative possibilities for an interpretation: either a narrow resonance at 1.42(10) MeV (Gamma = 1.11(76) MeV) superimposed on a correlated background, or two overlapping resonances, a ground state at 1.54(11) MeV (Gamma = 1.91(41) MeV) together with an excited state at 3.99(26) MeV (Gamma = 1.64(89) MeV). The two possible interpretations are discussed. (C) 2010 Elsevier B.V. All rights reserved.

borromean-nuclei

li-11

2p)

relative energy spectra

n2p)

deduced resonance state parameters

fragmentation

ground-state

model

E=280 MeV/nucleon

spectroscopy

halo

he-10

measured fragment spectra

(fragment) (neutron)-coin

NUCLEAR REACTIONS H-1(Li-11

neutron spectra

nuclei

nuclear reactions

exotic nuclei

(Li-11

Author

Håkan T Johansson

Chalmers, Applied Physics, Subatomic Physics

Yuliya Aksyutina

Chalmers, Applied Physics, Subatomic Physics

T. Aumann

K. Boretzky

M. J. G. Borge

A. Chatillon

L. V. Chulkov

D. Cortina-Gil

U. D. Pramanik

H. Emling

Christian Forssen

Chalmers, Applied Physics, Subatomic Physics

H. O. U. Fynbo

H. Geissel

G. Ickert

Björn Jonson

Chalmers, Applied Physics, Subatomic Physics

R. Kulessa

C. Langer

Mattias Lantz

Chalmers, Applied Physics, Subatomic Physics

T. LeBleis

K. Mahata

Mikael Meister

Chalmers, Applied Physics, Subatomic Physics

G. Munzenberg

Thomas Nilsson

Chalmers, Applied Physics, Subatomic Physics

Göran Hugo Nyman

Chalmers, Applied Physics, Subatomic Physics

R. Palit

S. Paschalis

W. Prokopowicz

R. Reifarth

A. Richter

K. Riisager

G. Schrieder

H. Simon

K. Summerer

O. Tengblad

H. Weick

Mikhail Zhukov

Chalmers, Applied Physics, Subatomic Physics

Nuclear Physics A

0375-9474 (ISSN)

Vol. 842 15-32

Subject Categories

Subatomic Physics

Physical Sciences

Roots

Basic sciences

DOI

10.1016/j.nuclphysa.2010.04.006

More information

Latest update

5/31/2018