corner
corner
APS » Journals » Phys. Rev. Lett. » Volume 96 » Issue 25
< Previous Article | Next Article >

Phys. Rev. Lett. 96, 252502 (2006) [4 pages]

Observation of Strong Low-Lying E1 Strength in the Two-Neutron Halo Nucleus 11Li

Download: PDF (606 kB) Buy this article Export: BibTeX or EndNote (RIS)

T. Nakamura1, A. M. Vinodkumar1, T. Sugimoto1, N. Aoi2, H. Baba3, D. Bazin4, N. Fukuda2, T. Gomi2, H. Hasegawa3, N. Imai5, M. Ishihara2, T. Kobayashi6, Y. Kondo1, T. Kubo2, M. Miura1, T. Motobayashi2, H. Otsu6, A. Saito7, H. Sakurai2, S. Shimoura7, K. Watanabe6, Y. X. Watanabe5, T. Yakushiji6, Y. Yanagisawa2, and K. Yoneda2
1Department of Physics, Tokyo Institute of Technology, 2-12-1 O-Okayama, Meguro, Tokyo 152-8551, Japan
2RIKEN (The Institute of Physical and Chemical Research), 2-1 Hirosawa, Wako, Saitama 351-0198, Japan
3Department of Physics, Rikkyo University, 3-34-1, Nishi-Ikebukuro, Toshima, Tokyo 171-8501, Japan
4National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824-1321, USA
5High Energy Accelerator Research Organization (KEK), 1-1 Oho, Tsukuba, Ibaraki 305-0801, Japan
6Department of Physics, Tohoku University, 2-1 Aoba, Aramaki, Aoba, Sendai 980-8578, Japan
7CNS, University of Tokyo, RIKEN campus, Hirosawa 2-1, Wako, Saitama 351-0198, Japan

Received 10 April 2006; published 30 June 2006

See accompanying Physics Focus

An exclusive measurement has been made of the Coulomb dissociation of the two-neutron halo nucleus 11Li at 70  MeV/nucleon at RIKEN. Strong low-energy (soft) E1 excitation is observed, peaked at about Ex=0.6  MeV with B(E1)=1.42(18)  e2 fm2 for Erel≤3  MeV, which was largely missed in previous measurements. This excitation represents the strongest E1 transition ever observed at such low excitation energies. The spectrum is reproduced well by a three-body model with a strong two-neutron correlation, which is further supported by the E1 non-energy-weighted cluster sum rule.

© 2006 The American Physical Society

URL:
http://link.aps.org/doi/10.1103/PhysRevLett.96.252502
DOI:
10.1103/PhysRevLett.96.252502
PACS:
21.60.Gx, 25.60.Gc, 27.20.+n
 
< Previous Article | Next Article >