Eur. Phys. J. A (2003) 18: 1-4
https://doi.org/10.1140/epja/i2003-10024-4

Short Note

Pseudo-spin band in the odd-odd nucleus ¹⁷²Lu

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’Università 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, Italy
⁵ Institute of Experimental Physics, University of Warsaw, PL-00-681, Warszawa, Poland
⁶ Department of Physics, University of Notre Dame, Notre Dame, IN, USA

^* 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 and the emitted $\gamma$-radiation was detected with the GASP array. Two sequences of a new identical band have been observed with the transition energies in the favoured and unfavoured sequences being identical within $\approx 3$ keV at low spins and $\approx 1$ keV at high spins over the whole observed spin range. Aninterpretation as a pseudo-spin singlet band of $\pi 1/2^- [541] \otimes \nu 1/2^- [\widetilde{420}]$ configuration is proposed. It represents the best example of a pseudo-spin singlet band in normal deformed nuclei known until now.