DOI: 10.1140/epja/i2003-10002-x
In-beam
-ray spectroscopy of
:
First observation of a low-lying prolate band in Po isotopes
K. Van de Vel1, A.N. Andreyev1, 2, R.D. Page2, H. Kettunen3, P.T. Greenlees3, P. Jones3, R. Julin3, S. Juutinen3, H. Kankaanpää3, A. Keenan3, P. Kuusiniemi3, M. Leino3, M. Muikku3, P. Nieminen3, P. Rahkila3, J. Uusitalo3, K. Eskola4, A. Hürstel5, M. Huyse1, Y. Le Coz5, M.B. Smith6, P. Van Duppen1 and R. Wyss7
1 Instituut voor Kern- en Stralingsfysica, University of Leuven, Belgium
2 Oliver Lodge Laboratory, Department of Physics, University of Liverpool, UK
3 Department of Physics, University of Jyväskylä, Finland
4 Department of Physics, University of Helsinki, Finland
5 DAPNIA/SPhN, CEA Saclay, France
6 Department of Physics and Astronomy, Rutgers University, USA
7 Department of Physics, Royal Institute of Technology, Stockholm, Sweden
karen.vandevel@fys.kuleuven.ac.be
(Received: 10 January 2003 / Revised version: 19 February 2003 / Published online: 7 May 2003)
Abstract
Gamma rays from excited states of
190Po have been
observed using the Jurosphere Ge-detector array coupled
to the RITU gas-filled separator. They were associated with a collective
band which from spin
onwards resembles
the prolate rotational bands known in the isotones
188Pb and
186Hg. This indicates that in
190Po the
prolate configuration becomes yrast above
.
The experimental results are interpreted in a two-band mixing
calculation and are in agreement with
-decay data and potential
energy surface calculations.
23.20.Lv - Gamma transitions and level energies.
25.70.-z - Low and intermediate energy heavy-ion reactions.
27.80.+w -

21.60.Ev - Collective models.
© Società Italiana di Fisica, Springer-Verlag 2003