2019 Impact factor 2.176
Hadrons and Nuclei


Eur. Phys. J. A 10, 135-138

Depopulation of the $\bf {J^{\pi}=9^-}$ isomer in $\bf {^{180}Ta}$ to the $\bf {J^{\pi}=1^+}$ ground state by Coulomb excitation

Ch. Schlegel1, 2, P. von Neumann-Cosel1, J. de Boer3, J. Gerl2, M. Kaspar2, I. Kozhoukharov2, M. Loewe3, H.J. Maier3, P.J. Napiorkowsky4, I. Peter2, M. Rejmund2, A. Richter1, H. Schaffner2, J. Srebrny5, M. Würkner3, H.J. Wollersheim2 and the EBGSI96-Collaboration5

1  Institut für Kernphysik, Technische Universität Darmstadt, D-64289 Darmstadt, Germany
2  Gesellschaft für Schwerionenforschung, Planckstrasse 1, D-64291 Darmstadt, Germany
3  Sektion Physik, Universität München, D-85748 Garching, Germany
4  Heavy Ion Laboratory, Warsaw University, PL-02-093 Warsaw, Poland
5  Institute of Experimental Physics, Warsaw University, ul. Hoza 69, PL-00-681 Warsaw, Poland

vnc@ikp.tu-darmstadt.de

(Received: 23 January 2001 Communicated by D. Schwalm)

Abstract
In-beam Coulomb excitation of the exotic odd-odd nucleus 180Ta has been studied by using a 136Xe beam and a setup consisting of five EUROBALL CLUSTER detectors and the Darmstadt-Heidelberg Crystal Ball array. Spectroscopic information on the extremely rare 180Ta is obtained from the comparison between an enriched ($3.6\pm0.3$% 180Ta) and a natural tantalum target. Possible evidence for a depopulation from the long-lived high-spin $J^\pi = 9^-$ isomer to the short-lived $J^\pi = 1^+$ ground state is searched for by different methods. The decay of low-K bandheads, which are nanosecond isomers, towards the ground-state band can be demonstrated in delayed spectroscopy. A $\gamma \gamma$ coincidence analysis provides indications of K = 5 in-band transitions. Finally, when the Crystal Ball is used as an energy and $\gamma$ multiplicity filter, signals of decay into the K = 0 band are observed.

PACS
25.70.De - Coulomb excitation.
27.70.+q - $150 \leq A \leq 189$ .
23.90.+w - Other topics in radioactive decay and in-beam spectrospcopy.

© Società Italiana di Fisica, Springer-Verlag 2001