The unbound isotopes He-9,He-10
Artikel i vetenskaplig tidskrift, 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.

deduced resonance state parameters

(fragment) (neutron)-coin

n2p)

E=280 MeV/nucleon

ground-state

halo

li-11

(Li-11

spectroscopy

nuclei

borromean-nuclei

fragmentation

he-10

2p)

exotic nuclei

NUCLEAR REACTIONS H-1(Li-11

relative energy spectra

model

measured fragment spectra

nuclear reactions

neutron spectra

Författare

Håkan T Johansson

Chalmers, Teknisk fysik, Subatomär fysik

Yuliya Aksyutina

Chalmers, Teknisk fysik, Subatomär fysik

T. Aumann

K. Boretzky

M. J. G. Borge

A. Chatillon

L. V. Chulkov

D. Cortina-Gil

U. D. Pramanik

H. Emling

Christian Forssen

Chalmers, Teknisk fysik, Subatomär fysik

H. O. U. Fynbo

H. Geissel

G. Ickert

Björn Jonson

Chalmers, Teknisk fysik, Subatomär fysik

R. Kulessa

C. Langer

Mattias Lantz

Chalmers, Teknisk fysik, Subatomär fysik

T. LeBleis

K. Mahata

Mikael Meister

Chalmers, Teknisk fysik, Subatomär fysik

G. Munzenberg

Thomas Nilsson

Chalmers, Teknisk fysik, Subatomär fysik

Göran Hugo Nyman

Chalmers, Teknisk fysik, Subatomär fysik

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, Teknisk fysik, Subatomär fysik

Nuclear Physics A

0375-9474 (ISSN)

Vol. 842 15-32

Ämneskategorier

Subatomär fysik

Fysik

Fundament

Grundläggande vetenskaper

DOI

10.1016/j.nuclphysa.2010.04.006