Speaker
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.
