Related papers: Cluster states and isoscalar monopole transitions …
Nuclei in the $sd$-shell demonstrate a remarkable interplay of cluster and mean-field phenomena. The $N=Z$ nuclei, such as $^{24}$Mg and $^{28}$Si, have been the focus of the theoretical study of both these phenomena in the past. The…
The structures of the ground and excited states of 12Be were studied with antisymmetrized molecular dynamics. The ground state was found to be a state with a developed 2-alpha core with two neutrons occupying the intruder orbits. The energy…
Background: A recent inelastic alpha-scattering experiment [Phys. Rev. Lett. 129, 102701 (2022)] found $0^+$ resonances in $^{24}$Mg on and above the $^{12}$C+$^{12}$C break-up threshold. It has been conjectured that the states have a…
The relation between the monopole transition strength and existence of cluster structure in the excited states is discussed based on an algebraic cluster model. The structure of $^{12}$C is studied with a 3$\alpha$ model, and the wave…
We investigate excited states of $^{18}$O by using the antisymmetrized molecular dynamics. It is found that five different types of cluster states exist which we call ${}^{14}{\rm C}+\alpha$, higher-nodal ${}^{14}{\rm C}+\alpha$, two…
The structure of $3/2^{-}$ and $1/2^{+}$ states in $^{11}$B is investigated with an $\alpha+\alpha+t$ orthogonality condition model (OCM) based on the Gaussian expansion method. Full levels up to the $3/2^{-}_{3}$ and $1/2^{+}_2$ states…
Isoscalar (IS) monopole and dipole excitations in $^{16}$O were investigated by the method of shifted basis antisymmetrized molecular dynamics combined with the generator coordinate method. Significant strengths of the IS monopole and…
The alpha cluster states of 16C are investigated by using the antisymmetrized molecular dynamics. It is shown that two different types of alpha cluster states exist: triangular and linear-chain states. The former has an approximate…
We report an investigation of the structure of $^{12}$C nucleus employing a newly developed configuration-mixing method. In the three-dimensional coordinate-space representation, we generate a number of Slater determinants with various…
The longstanding problem of characterization of the $0^+_2$ states in Gd isotopes is revisited by adopting the Nilsson$+$BCS mean field and the random-phase approximation. The interband electric quadrupole transition strengths varying…
We study the $\alpha + \alpha + {}^{3}$He cluster structure of ${}^{11}$C within the microscopic cluster model. The calculations essentially reproduce the energy spectra for both negative and positive parity states, particularly the…
We study structures of the $0^+$ states of $^{13}_\Lambda$C within the framework of $\alpha+\alpha+\alpha+\Lambda$ four-body orthogonality condition model with the Gaussian expansion method. We obtain five $0^+$ states of $^{13}_\Lambda$C…
Gamov-Teller transitions from the $^{14}$N ground state to the $^{14}$C ground and excited states were investigated, based on the model of antisymmetrized molecular dynamics. The calculated strengths for the allowed transitions to the…
We investigate the cluster configurations in Li isotopes, which are described in the optimization of the multi-Slater determinants of the antisymmetrized molecular dynamics. Each Slater determinant in the superposition is determined…
The Generalized Coherent State Model, proposed previously for a unified description of magnetic and electric collective properties of nuclear systems, is used to study the ground state band charge density as well as the E0 transitions from…
Excited states of $^4$He are studied in four-body calculations with explicitly correlated Gaussian bases. All the levels below $E_{\rm x}$=26 MeV are reproduced reasonably well using realistic potentials. An analysis is made to show how the…
Electromagnetic transitions from deformed structures based on $\alpha$ configurations or on heavier clusters are discussed, drawing the link between multiparticle-multihole excited bands and cluster structures. Enhanced E2 and E1…
We investigate the existence of weakly coupled gas-like states comprised of three $\alpha$ particles around an $^{16}$O core in $^{28}$Si. We calculate the excited states in $^{28}$Si using the multi-configuration mixing method based on the…
A cluster-transfer experiment of $^9\rm{Be}(^9\rm{Be},^{14}\rm{C}\rightarrow\alpha+^{10}\rm{Be})\alpha$ at an incident energy of 45 MeV was carried out in order to investigate the molecular structure in high-lying resonant states in…
Recently, we have determined surface distributions of $\alpha$ clusters in the ground state of $^{20}\mathrm{Ne}$ from $\alpha$-transfer cross sections, without investigating the properties of its excited states. In this paper we extend our…