https://doi.org/10.1140/epja/i2019-12856-5
Regular Article - Experimental Physics
Longitudinal wobbling in 133La
1
Department of Nuclear and Atomic Physics, Tata Institute of Fundamental Research, Colaba, 400 005, Mumbai, India
2
University of Notre Dame, 46556, Notre Dame, IN, USA
3
Department of Physics, University of Kashmir, 190 006, Srinagar, India
4
Cluster University of Srinagar, 190001, Srinagar, Jammu and Kashmir, India
5
Department of Physics, Panjab University, 160014, Chandigarh, India
* e-mail: palit@tifr.res.in
Received:
29
April
2019
Accepted:
14
August
2019
Published online:
20
September
2019
Excited states of 133La have been investigated to search for the wobbling excitation mode in the low-spin regime. Wobbling bands with 
and 1 are identified along with the interconnecting 
, E2 transitions, which are regarded as one of the characteristic features of wobbling motion. An increase in wobbling frequency with spin implies longitudinal wobbling for 133La, in contrast with the case of transverse wobbling observed in 135Pr. This is the first observation of a longitudinal wobbling band in nuclei. The experimental observations are accounted for by calculations using the quasiparticle-triaxial-rotor (QTR) model, which attribute the appearance of longitudinal wobbling to the early alignment of a 
proton pair.
© Società Italiana di Fisica and Springer-Verlag GmbH Germany, part of Springer Nature, 2019
