Fast timing for nuclear structure and applications - FAST'26

Fast-timing lifetime measurements in the 176Yb and 178Yb isotopes

28 Apr 2026, 14:45

4m

Training and Conference Center (CCI) ( Horia Hulubei National Institute for R&D in Physics and Nuclear Engineering (IFIN-HH))

Poster Nuclear structure from fast-timing measurements Day 2

Speaker

P. Koseoglou (Department of Physics, National and Kapodistrian University of Athens, Zografou Campus, GR-15784 Athens, Greece)

Description

All rare-earth isotopic chains are known to undergo a transition from spherical to deformed shapes between the magic neutron number N = 82 and the neutron mid-shell region around neutron number N = 104. Both $^{176}$Yb and $^{178}$Yb isotopes (with N = 106 and 108, respectively) show signs of strong deformation, standing on the deformed side of the ytterbium isotopic chain, with R$_{4/2}$ = E$_{4^+_1}$/E$_{2^+_1}$ values close to the 3.33 benchmark value of a rigid-rotor nucleus. An experiment was carried out in the 10 MV FN Tandem accelerator of the Institut für Kernphysik at the University of Cologne to study the deformation evolution in the ytterbium isotopic chain through $\gamma$-spectroscopy and lifetime measurements in $^{176}$Yb and $^{178}$Yb isotopes. The lifetime of the E$_{2^+_1}$ excited state in $^{176}$Yb was remeasured, whereas in $^{178}$Yb it was measured for the first time. The preliminary results of the lifetime analysis, using fast-timing techniques, will be presented in this poster contribution together with the $\gamma$-spectroscopic findings, which set $^{178}$Yb as the most rigid-rotor-like isotope in its isotopic chain.

This work is supported by the German Research Foundation – 539757749.