Eur. Phys. J. A (2004) 20: 375-379
https://doi.org/10.1140/epja/i2004-10018-8

Letter

Signature inversion in the semidecoupled band of the odd-odd nucleus ¹⁷² Lu

¹ Institut für Kernphysik, Forschungszentrum Jülich, D-52425, Jülich, Germany
² Institute of Nuclear Research and Nuclear Energy, Bulgarian Academy of Sciences, BG-1784, Sofia, Bulgaria
³ Dipartimento di Fisica dell’Universitá and Istituto Nazionale di Fisica Nucleare, Sezione di Padova, I-35131, Padova, Italy
⁴ Laboratori Nazionali di Legnaro, Istituto Nazionale di Fisica Nucleare, I-35020, Legnaro (Padova), Italy
⁵ Institute of Experimental Physics, University of Warsaw, PL-00-681, Warszawa, Poland

^* e-mail: r.lieder@fz-juelich.de

Abstract

High-spin states in the odd-odd nucleus ¹⁷²Lu have been populated in a ¹⁷⁰Er(⁷Li,5n) reaction at 51 MeV and the emitted -radiation was detected with the GASP array. A new semidecoupled band with the proposed configuration has been established exhibiting a signature inversion. A systematic study of the signature inversion in odd-odd nuclei of the rare-earth region is presented. The variation of the inversion spin remains nearly constant for nuclei with the same N-Z, increases with N for an isotopic chain and decreases with Z for an isotonic chain. On the basis of the systematics a change of the spins by is proposed for the semidecoupled bands in ¹⁸⁰Re, ^182,184Ir and ^184,186Au.