Short note
Alpha decay of the new isotopes 188,189Po
A.N. Andreyev1 - D. Ackermann2 - P. Cagarda3 - J. Gerl2 -
F. Heberger2 - S. Hofmann2 - M. Huyse1 - A. Keenan4 -
H. Kettunen5 - A. Kleinböhl2 - A. Lavrentiev6 - M. Leino5 - B. Lommel2 -
M. Matos3 - G. Münzenberg2 - C. Moore4 - C.D. O'Leary4 - R.D. Page4 -
S. Reshitko2 - S. Saro3 - C. Schlegel2 - H. Schaffner2 - M. Taylor4 -
P. Van Duppen1 - L. Weissman1 - R. Wyss7
1 Instituut voor Kern- en Stralingsfysica, University of Leuven, Celestijnenlaan 200 D,
3001 Leuven, Belgium
2 Gesellschaft fur Schwerionenforschung Darmstadt, Postfach 110541, 6100 Darmstadt, Germany
3 Department of Nuclear Physics,Comenius University, Bratislava, Slovakia
4 Department of Physics, Oliver Lodge Laboratory, University of Liverpool, Liverpool L69 7ZE, UK
5 Department of Physics, University of Jyväskylä, 40351 Jyväskylä, Finland
6 Flerov Laboratory of Nuclear Reactions, Joint Institute for Nuclear Research, 141980, Dubna, Russia
7 Department of Physics, Royal Institute of Technology, 104 05 Stockholm, Sweden
Received: 15 October 1999 Communicated by J. Äystö
Abstract
New neutron-deficient isotopes
188,189Po have been produced
in the complete fusion reaction of 52Cr ions with a 142Nd
target at the velocity filter SHIP. The evaporation residues were
separated in-flight and subsequently identified on the basis of
and
-conversion electron coincidence
measurements and of
-
position and time correlations. In
189Po a ground state to ground state
decay with
E
=7540(20) keV, T1/2=5(1) ms and two fine structure
-decays at E
=7264(15) keV and E
=7316(15)
keV have been observed. In 188Po (T1/2=400
+200-150
s ) a ground state to ground state
decay at
E
=7915(25) keV and a fine structure
decay at
E
=7350(40) keV have been found. Improved data on the
-decay of 189Bi were obtained.
PACS
23.60.+e
decay -
27.70.+q
-
27.80.+w
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