Low-Energy Electron Scattering for Nucleon and Exotic Nuclei (LEES2024)

Triaxiality of 154Sm by Low Energy Electron Inelastic Scattering

Oct 29, 2024, 6:00 PM

2h

TOKYO ELECTRON House of Creativity (東北大学知の館), Tohoku University

Poster

Speaker

Kengo Hotta (RARIS, Tohoku University)

Description

In the 1950s, Bohr and Mottelson established the picture that most of heavy atomic nuclei deform into a prolate shape consisting of one long axis and two short axes of equal length. However, recent theoretical calculations by T. Otsuka et al. indicate that these nuclei prefer a triaxial shape, with all three axes having different lengths. Additionally, the presence of excited states due to rotational bands in the short-axis plane caused by triaxial asymmetry has also been suggested.
While ${}^{154}$Sm has long been regarded as a prolate nucleus, calculations by T. Otsuka et al. show that it weakly deforms into a triaxial shape, suggesting the existence of an excited state, $2_{g\gamma }^{+}$, around $E_x$ = 2.7 MeV. By measuring this excited state through low-energy electron scattering, we can determine that the total angular momentum of this excited state is $J=2$ by the momentum transfer dependence of the form factor. An experiment to measure this excited state is planned at RARiS, Tohoku University, with a test experiment scheduled in November. I will discuss the feasibility of measuring the $2_{g\gamma }^{+}$ state at Tohoku University and future studies.