Related papers: Cluster and toroidal aspects of isoscalar dipole e…
Among the states of $^{12}$C, there is an important subset of $K$=0 and $K$=$I$ planar intrinsic states in which the intrinsic motion of the nucleons are confined in the planar region defined by the three-alpha cluster or by their generated…
Cluster multipole orderings composed of atomic high-rank multipole moments are theoretically investigated with a 5$d$-electron compound Ca$_5$Ir$_3$O$_{12}$ in mind. Ca$_5$Ir$_3$O$_{12}$ exhibits two hidden orders: One is an…
Novel equations for the electric dipole polarizability $\alpha_{_{E1}}$ of low-lying excited states in atomic nuclei -- and the related $(-2)$ moment of the total photo-absorption cross section, $\sigma_{_{-2}}$ -- are inferred in terms of…
The energy spectrum of the $^{12}C$ nucleus with $(J^{\pi}, T)=(0^+,0)$ and $(2^+,0)$ is investigated in the framework of the multicluster dynamical model by using a deep $\alpha \alpha$-potential with forbidden states in the S and D waves.…
Structures of excited states in $^{11}$B are investigated with a method of $\beta$-$\gamma$ constraint antisymmetrized molecular dynamics in combination with the generator coordinate method. Various excited states with developed cluster…
Background: Two new $J^\pi=0^+$ states are recently observed around a few MeV above the Hoyle state (the second $0^+$ state in 12C). The characters of them are only poorly discussed in theory and are still mysterious. Purpose: I give for…
A toroidal dipole represents an often overlooked electromagnetic excitation distinct from the standard electric and magnetic multipole expansion. We show how a simple arrangement of strongly radiatively coupled atoms can be used to…
Isoscalar monopole transitions from the ground states to cluster states in $\Be$ and $\Li$ are investigated with $\He+\alpha$ and $\He+t$ cluster models, respectively. In $\Be$, significant monopole strengths to $\He+\alpha$ cluster…
A comparative analysis of toroidal, compressional and vortical dipole strengths in the spherical $^{144}$Sm and the deformed $^{154}$Sm is performed within the random-phase-approximation using a set of different Skyrme forces. Isoscalar…
Studies of the 16O(9Be,alpha 7Be)14C, 7Li(9Be,alpha 7Li)5He and 7Li(9Be,alpha alpha t)5He reactions at E(beam)=70 and 55 MeV have been performed using resonant particle spectroscopy techniques. The 11C excited states decaying into…
The dipole in the angular distribution of the cosmic microwave background (CMB) is attributed to the Doppler effect and our motion relative to the CMB rest frame. It is expected that observations of large-scale structures (LSSs) would also…
Isoscalar dipole nuclear response reveals the low- and high-energy resonances. The nature of isoscalar dipole resonances in heavy spherical nuclei is studied by using the translation-invariant kinetic model of small oscillations of finite…
Collective monopole vibrations are studied in the framework of an antisymmetrized version of molecular dynamics as a function of the vibration amplitude. The giant monopole resonance energy in ${}^{40}Ca$ is sensitive to the…
Background: Cluster states in $^{13}$N are extremely difficult to measure due to the unavailability of $^{9}$B+$\alpha$ elastic scattering data. Purpose: Using $\beta$-delayed charged-particle spectroscopy of $^{13}$O, clustered states in…
Inelastic proton scattering experiments were performed at the Research Center for Nuclear Physics, Osaka, with a 295 MeV beam covering laboratory angles 0{\deg}-6{\deg} and excitation energies 6-22 MeV. Cross sections due to E1 and M1…
We calculate $^3$He+$p$ scattering phase shifts in two different microscopic cluster models, Model T and Model C, in order to show the effects of tensor force as well as $D$-wave components in the cluster wave function. Model T employs a…
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…
A remarkable orbital quadrupole magnetic resonance, so-called twist mode, is predicted in alkali metal clusters where it is represented by $I^{\pi}=2^-$ low-energy excitations of valence electrons with strong M2 transitions to the ground…
We compute the electric dipole polarizability of 48Ca with an increased precision by including more correlations than in previous studies. Employing the coupled-cluster method we go beyond singles and doubles excitations and include…
Isoscalar giant resonances are nuclear collective excitations associated with the oscillation in phase of protons and neutrons according to a certain multipolarity $L$. In particular, the isoscalar giant monopole resonance ($L=0$) is the…