Two-quasiparticle and collective excitations in transitional 108,110 Pd nuclei

S. Lalkovski; A. Minkova; M.-G. Porquet; A. Bauchet; I. Deloncle; A. Astier; N. Buforn; L. Donadille; O. Dorvaux; B. P. J. Gall; R. Lucas; M. Meyer; A. Prévost; N. Redon; N. Schulz; O. Stézowski

doi:10.1140/epja/i2003-10098-x

EPJ

Two-quasiparticle and collective excitations in transitional ^108,110 Pd nuclei

S. Lalkovski¹^,2^*, A. Minkova¹^,2^,3, M.-G. Porquet¹, A. Bauchet¹, I. Deloncle¹, A. Astier⁴, N. Buforn⁴, L. Donadille⁵, O. Dorvaux⁶, B. P. J. Gall⁶, R. Lucas⁷, M. Meyer⁴, A. Prévost⁴, N. Redon⁴, N. Schulz⁶ and O. Stézowski⁴

¹ CSNSM IN2P3-CNRS and Université Paris-Sud, 91405, Orsay, France
² University of Sofia St. Kliment Ohridski, 1126, Sofia, Bulgaria
³ INRNE, Bulgarian Academy of Sciences, 1784, Sofia, Bulgaria
⁴ IPNL, IN2P3-CNRS and Université Claude Bernard, 69622, Villeurbanne Cedex, France
⁵ University of Birmingham, Birmingham, UK
⁶ IReS, IN2P3-CNRS and Université Louis Pasteur, 67037, Strasbourg, France
⁷ Commissariat á l’Énergie Atomique, CEA/Saclay, DSM/DAPNIA/SPhN, 91191, Gif-sur-Yvette Cedex, France

Abstract

High-spin states in ^108,110Pd isotopes are studied by $\gamma$ -ray spectroscopy of heavy-ion-induced fission. The Pd isotopes are produced in the fission channel of the ³¹P + ¹⁷⁶Yb reaction at beam energy 152 MeV. The prompt $\gamma$ -rays are detected with the EUROBALL4 multidetector array. The yrast states of ^108,110Pd have been observed above the region of the first backbend. The level scheme of ¹⁰⁸Pd was extended with a new negative-parity band. The yrast sequence in ¹¹⁰Pd is observed up to spin I = 14⁺ and negative-parity bands have also been identified. The backbending in these even-mass Pd isotopes is associated with the alignment of the neutron (h _11/2)² pair. The negative-parity states arise from two neutron configurations $\nu h_{11/2} \otimes \nu g_{7/2}$ and $\nu h_{11/2} \otimes \nu d_{5/2}$ and they are interpreted in the frame of two-quasiparticle + rotor model as semidecoupled bands. The observed experimental staggering in the $\gamma$ -bands of ^108,110Pd supports the theoretical predictions for $\gamma$ -instability of their shapes.

12 Internat. Congress of the Balkan Physical Union
July 8-12, 2025
Bucharest, Romania

EPJ

Two-quasiparticle and collective excitations in transitional 108,110 Pd nuclei

Conference announcements

Two-quasiparticle and collective excitations in transitional ^108,110 Pd nuclei