Eur. Phys. J. A 13, 297-305 (2002)

Development of magnetic rotation in light Gd nuclei; study of

R.M. Lieder^{1, 2}, T. Rzaca-Urban², H. Brands¹, W. Gast¹, H.M. Jäger¹, L. Mihailescu¹, Z. Marcinkowska², W. Urban², T. Morek², Ch. Droste², P. Szymanski², S. Chmel³, D. Bazzacco⁴, G. Falconi⁴, R. Menegazzo⁴, S. Lunardi⁴, C. Rossi Alvarez⁴, G. de Angelis⁵, E. Farnea⁵, A. Gadea⁵, D.R. Napoli⁵, Z. Podolyak⁵, Ts. Venkova⁶ and R. Wyss<sup>7

1</sup>  Institut für Kernphysik, Forschungszentrum Jülich, D-52425 Jülich, Germany
²  Institute of Experimental Physics, University of Warsaw, PL-00-681 Warszawa, Poland
³  Institut für Strahlen- und Kernphysik, University of Bonn, D-53115 Bonn
⁴  Dipartimento di Fisica dell'Università and Istituto Nazionale di Fisica Nucleare, Sezione di Padova, I-35131 Padova, Italy
⁵  Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali di Legnaro, I-35020 Legnaro, Italy
⁶  Institute of Nuclear Research and Nuclear Energy, Bulgarian Academy of Sciences, BG-1784 Sofia, Bulgaria
⁷  Royal Institute of Technology, Physics Department Frescati, S-10405 Stockholm, Sweden

r.lieder@fz-juelich.de

(Received: 9 December 2001 / Revised version: 17 December 2001 Communicated by D. Schwalm )

Abstract
High-spin states in ¹⁴²Gd have been populated by means of the ⁹9Ru( ⁴8Ti,2p3n) reaction at 240 MeV and investigated with the -spectrometer EUROBALL III and the charged-particle detector array ISIS. The features of four dipole bands have been determined and compared with tilted-axis cranking model calculations indicating that they are magnetic rotational bands. A transition from regular to irregular bands has been found approaching N = 82 demonstrating that this is a general phenomenon in nuclei near a double-shell closure.

PACS
21.10.Re - Collective levels.
21.60.Ev - Collective models.
23.20.En - Angular distribution and correlation measurements.
27.60.+j - .

© Società Italiana di Fisica, Springer-Verlag 2002