https://doi.org/10.1140/epja/i2008-10621-7
Regular Article-Experimental Physics
E2 transition probabilities in the decoupled band of the 129La nucleus
1
Nuclear Physics Division, IEP, University of Warsaw, Hoża 69, 00-681, Warsaw, Poland
2
Heavy Ion Laboratory, University of Warsaw, Pasteura 5a, 02-093, Warsaw, Poland
3
Cyclotron Laboratory, A.F. Ioffe Physical Technical Institute, 194021, St.-Petersburg, Russia
4
Institute of Theoretical Physics, University of Warsaw, Hoża 69, 00-681, Warsaw, Poland
5
The A. Sołtan Institute for Nuclear Studies, 05-400, Świerk, Poland
Received:
10
March
2008
Revised:
19
May
2008
Published online:
29
July
2008
Lifetimes of the yrast levels with spins Iπ = 23/2− to 39/2− in 129La produced via the 120Sn(14N, 5n) reaction at a beam energy of 77MeV have been measured by the Doppler shift attenuation method. The properties of the studied levels belonging to the πh11/2 band were compared with the theoretical predictions obtained in the framework of the core quasi-particle coupling model. It is suggested that the rigid-rotor model used to describe the cores is too simplified as the even-even nuclei from the A ∼ 130 region are susceptible to shape deformation. Reasonable agreement was obtained with the phenomenological cores based on the experimental data of 128Ba.
PACS: 21.10.Tg Lifetimes, widths – / 21.60.Ev Collective models – / 27.60.+j 90 ≤ A ≤ 149 –
© SIF, Springer-Verlag Berlin Heidelberg 2008
