Eur. Phys. J. A (2008) 35: 135-158
https://doi.org/10.1140/epja/i2007-10533-0

Regular Article - Experimental Physics

Investigation of lifetimes in quadrupole bands of ¹⁴²Gd

¹ Institut für Kernphysik, Forschungszentrum Jülich, D-52425, Jülich, Germany
² iThemba LABS, P.O. Box 722, 7129, Somerset West, South Africa
³ A.F. Ioffe Physical Technical Institute RAS, RU-194021, St. Petersburg, Russia
⁴ Physical Institute, St. Petersburg State University, RU-198904, St. Petersburg, Russia
⁵ Division of Mathematical Physics, LTH, Lund University, SE-221 00, Lund, Sweden
⁶ Institute of Nuclear Research and Nuclear Energy, Bulgarian Academy of Sciences, BG-1784, Sofia, Bulgaria
⁷ Institute of Experimental Physics, University of Warsaw, PL-00-681, Warszawa, Poland
⁸ Institut für Strahlen- und Kernphysik, University of Bonn, D-53115, Bonn, Germany
⁹ Laboratori Nazionali di Legnaro, Istituto Nazionale di Fisica Nucleare, I-35020, Legnaro, Italy
¹⁰ Dipartimento di Fisica dell'Università and Istituto Nazionale di Fisica Nucleare, Sezione di Padova, I-35131, Padova, Italy
¹¹ Institut de Recherches Subatomique IReS, F-67037, Strasbourg, France
¹² Institut für Kernphysik, Universität zu Köln, D-50937, Köln, Germany

^* e-mail: lieder@tlabs.ac.za

Received: 15 August 2007
Accepted: 11 February 2008
Published online: 10 March 2008

Abstract

For a level scheme investigation of ¹⁴²Gd an experiment with the γ -spectrometer EUROBALLIII has been carried out and lifetimes have been measured with EUROBALL IV using the Doppler-shift attenuation method. The high-spin states have been populated in these experiments by means of the ⁹⁹Ru(⁴⁸Ti, 2p3n) reaction at a beam energy of 240MeV and the ¹¹⁴Sn(³²S, 2p2n) reaction at 160MeV, respectively. Reduced E2 transition probabilities B(E2) were determined for 15 members of four quadrupole bands. For the interpretation of the positive-parity even-spin quadrupole bands, calculations in the cranked Nilsson-Strutinsky as well as interacting boson models have been performed. From the former calculations it was concluded that the high-spin states of the (+ , 0)₁ band in ¹⁴²Gd represent a triaxial nucleus rotating around the longest principal axis.