The strength of octupole correlations in neutron-rich Xe isotopesW. Urban1, T. Rzaca-Urban1, N. Schulz2, J.L. Durell3, W.R. Phillips3, A.G. Smith3, B.J. Varley3 and I. Ahmad4
1 Institute of Experimental Physics, Warsaw University, ul.Hoza 69, 00-681 Warszawa, Poland
2 Institut de Recherches Subatomiques UMR7500, CNRS-IN2P3 and Université Louis Pasteur, 67037 Strasbourg, France
3 Schuster Laboratory, Department of Physics and Astronomy, University of Manchester, Manchester M13 9PL, UK
4 Argonne National Laboratory, Argonne, IL 60439, USA
(Received: 18 November 2002 / Published online: 25 February 2003)
Excited levels in 140Xe and 142Xe nuclei, populated in the spontaneous fission of 248Cm, were studied by means of prompt -ray spectroscopy, using EUROGAM2 array. We report the first observation of an octupole band in 142Xe and extend the octupole band in 140Xe. Level schemes of 140Xe and 142Xe obtained in this work show patterns characteristic of ocupole-vibrational bands. Properties of octupole bands in Xe isotopes indicate that octupole correlations in these nuclei are lower than in the corresponding Ba nuclei. The electric dipole moment of 142Xe was found to be larger than in other Xe isotopes, contrary to theoretical predictions. This may be due to the special role of the N=88 neutron number.
23.20.Lv - Gamma transitions and level energies.
21.60.Cs - Shell model.
25.85.Ca - Spontaneous fission.
27.60.+j - .
© Società Italiana di Fisica, Springer-Verlag 2003