Phys. Rev. Lett. 88, 082501 (2002) [4 pages]Hypernuclear Fine Structure in Λ9Be |
H. Akikawa1, S. Ajimura2, R. E. Chrien3, P. M. Eugenio4, G. B. Franklin4, J. Franz5, L. Gang6, K. Imai1, P. Khaustov4, M. May3, P. H. Pile3, B. Quinn4, A. Rusek3, J. Sasao7, R. I. Sawafta8, H. Schmitt5, H. Tamura7, L. Tang6, K. Tanida9, L. Yuan6, S. H. Zhou10, L. H. Zhu1,10, and X. F. Zhu10
1Department of Physics, Kyoto University, Kyoto 606-8502, Japan
2Department of Physics, Osaka University, Toyonaka 560-0043, Japan
3Brookhaven National Laboratory, Upton, New York 11973
4Department of Physics, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213
5Department of Physics, University of Freiburg, Freiburg D-79104, Germany
6Department of Physics, Hampton University, Hampton, Virginia 23668
7Department of Physics, Tohoku University, Sendai 980-8578, Japan
8Physics Department, North Carolina A&T State University, Greensboro, North Carolina 27411
9Department of Physics, University of Tokyo, Tokyo 113-0033, Japan
10Department of Nuclear Physics, China Institute of Atomic Energy, Beijing 102413, China
Received 6 November 2001; published 11 February 2002
With a germanium detector array (Hyperball), we observed two γ-ray peaks corresponding to the two transitions ( 5/2+→1/2+ and 3/2+→1/2+) in the Λ9Be hypernucleus which was produced by the 9Be(K-,π-) reaction. The energies of the γ rays are 3029±2±1 keV and 3060±2±1 keV. The energy difference was measured to be 31.4-3.6+2.5 keV, which indicates a very small Λ-spin-dependent spin-orbit force between a Λ and a nucleon. This is the smallest level splitting by far ever measured in a hypernucleus.
©2002 The American Physical Society
URL: http://link.aps.org/abstract/PRL/v88/e082501
DOI: 10.1103/PhysRevLett.88.082501
PACS: 21.80.+a, 13.75.Ev, 23.20.Lv, 25.80.Nv
[ Abstract | Previous article | Next article | Issue 8 ]
About PROLA | Terms and Conditions | Subscriptions | Search | Help
Content in PROLA © 2008 by The American Physical Society All rights reserved. PROLA™ is a trademark of The American Physical Society. Use of APS online journals implies that the user has read and agrees to the Terms and Conditions in the Subscription Agreement.