17–21 Jul 2023
MAISON MINATEC
Europe/Paris timezone

Microscopic aspects of $\gamma$-softness in atomic nuclei

20 Jul 2023, 17:00
15m
Amphitheater (MAISON MINATEC)

Amphitheater

MAISON MINATEC

Centre de Congrès Maison MINATEC 3 parvis Louis Néel 38054 Grenoble Cedex 9
Oral Theoretical Nuclear Structure Session 13A

Speaker

Stefan Frauendorf (Department of Physics, University of Notre Dame, Notre Dame,)

Description

How the collective features emerge from the microscopic degrees of freedom is one of the main research themes in quantum many-body systems. Using the microscopic approach of the triaxial projected shell model (TPSM), the authors demonstrate that  admixing few quasiparticle excitations into the vacuum configuration with a fixed triaxiality parameter $\gamma$ provides a quantitative description of the shape fluctuations of the $\gamma$-soft nuclei.
 This is demonstrated by a detailed study of $^{104}$Ru, which reproduces a large set of experimental energies and $BE2$ matrix elements measured by COULEX [1]. 
The collective features are elucidated using the quadrupole shape invariant analysis, and also the staggering phase classification of the $\gamma$-band. A systematic study of twenty-two nuclei has been
carried out by means of the TPSM. The experimental energies of the yrast bands and $\gamma$ bands as well as the pertaining experimental $B(E2)$ values for intra and inter band transitions are very well reproduced. The signatures of triaxiality softness, as the position of the $2^+_2$ state relative to the $4^+_1$ state, the energy staggering of the $\gamma$ band, the position of the $0^+_2$ state and its
E2 decay are discussed.
[1] N. Nazir et al. Phys. Rev. C 107, L021303 (2023)

Primary author

Stefan Frauendorf (Department of Physics, University of Notre Dame, Notre Dame,)

Co-authors

Javid Sheikh (Department of Physics, University of Kashmir) G. H. Bhat (Department of Physics, SP College ) S.P. Rouoof (Department of Physics, Islamic University of Science and Technology) Nazira Nazir (Department of Physics, University of Kashmir) S. Jehangir (Department of Physics, Islamic University of Science and Technology) N. Rather (Department of Physics, Islamic University of Science and Technology)

Presentation materials