Isoscalar dipole excitations inO16

Abstract

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 dipole transitions were obtained in the low-energy region below the giant resonances. In addition to the compressive mode, which mainly contributes to the high-energy strengths for the IS dipole giant resonance, we obtained a variety of low-energy dipole modes such as the vortical dipole mode in the 1 − 1 state of the vibrating tetrahedral 4α and the 12 C+α cluster structure in the 1 − 2 state. The 1 − 1 state contributes to the significant low-energy strength of the IS dipole transition as 5% of the energy-weighted sum rule, which describes well the experimental data observed by the α inelastic scattering.

Isoscalar monopole and dipole transitions inMg24,Mg26, andSi

“…The extracted IS1 and IS0 strength distributions were compared to the theoretical calculations performed within the Skyrme Quasiparticle Random-Phase-Approximation (QRPA) [48][49][50][51] and Antisymmetrized Molecular Dynamics + Generator Coordinate Method (AMD+GCM) [10][11][12][13][14] approaches. The correspondence, at least tentative, between some calculated and observed states was established.…”

“…The low-energy isoscalar monopole (IS0) and dipole (IS1) states in light nuclei can serve as fingerprints of clustering [5,6] one of the basic features of light nuclei. IS1 states can also deliver important information on some mean-field features, such as vorticity [7][8][9][10][11][12][13][14].…”

“…In addition to this clustering behaviour, mean-field structures may also exist. Individual low-lying vortical IS1 states were predicted within the Quasiparticle Random-Phase-Approximation (QRPA) [7][8][9] and the Antisymmetrized Molecular Dynamics + Generator Coordinate Method (AMD+GCM) [10][11][12][13][14]. These states should exist in 10 Be [10,11], 12 C [12], 16 O [13], 20 Ne [8], and 24 Mg [7][8][9]14].…”

Drastic change in inelastic scattering depending on the development of dineutron correlation in $^{10}$Be

“…The reliable and precise information is extracted from the experimental data by the development of the folding procedure and the effective NN interaction [34,43]. Recently, the characteristic behaviors of the cross section caused by the exotic structure and the property of the potential are predicted [43][44][45][46].…”

Microscopic calculation of inelastic proton scattering off O18, Be10, Be12Kanada-En’yo1, Ogata2 2019Phys. Rev. CSelf Cite14050View full textAdd to dashboardCite

“…[1]. For instance, in 18 O and 48 Ca, the ratio becomes significantly larger than N/Z, which indicates the neutron dominance in the 2 + 1 excitation because of the proton shell closure. The phenomena of the shape difference and/or the neutron dominance have been suggested also in unstable nuclei such as 10 Be, 12 Be, and 16 C [2][3][4][5][6][7][8][9][10][11][12][13][14][15].…”