Description of low-lying vibrational and two-quasiparticle states in164Dy

Testing Skyrme Energy-Density Functionals with the QRPA in Low-lying Vibrational States of Rare-Earth Nuclei

“…Reference [64], using the boson-expansion method, obtained B(E2)↑ = 0.130 e 2 b 2 in 154 Sm, a value somewhat larger than ours. Soloviev et al [65,66] Those transition probabilities are close to the experimental data (0.116 e 2 b 2 in 178 Hf [65]), and the fit of the interaction meant that energies were also reproduced well. See also Ref.…”

“…Early work on vibrations in rare-earth nuclei often made use of the pairing-plus-QQ (quadrupolequadrupole) Hamiltonian, both in the (Q)RPA [59][60][61][62][63] and in approximations that went beyond the QRPA order, e. g. [64][65][66]. Single-particle energies were usually obtained from the Nilsson potential, with slight shifts to improve phenomenology, and the strength of the QQ interactions was modified slightly from the self-consistent value so as to reproduce the energies of the γ-vibrational states.…”

Testing Skyrme energy-density functionals with the quasiparticle random-phase approximation in low-lying vibrational states of rare-earth nuclei

“…Reference [66], using the boson-expansion method, obtained B(E2)↑ = 0.130 e 2 b 2 in 154 Sm, a value somewhat larger than ours. Soloviev et al [67,68] used the quasiparticle-phonon nuclear model, which includes two-phonon couplings, and obtained B(E2) ↑ = 0.127 e 2 b 2 ( 168 Er), 0.042 e 2 b 2 ( 172 Yb), and 0.122 e 2 b 2 ( 178 Hf). Those transition probabilities are close to the experimental data (0.116 e 2 b 2 in 178 Hf [67]), and the fit of the interaction meant that energies were also reproduced well.…”

“…Early work on vibrations in rare-earth nuclei often made use of the pairing-plus-QQ (quadrupolequadrupole) Hamiltonian, both in the (Q)RPA [61][62][63][64][65] and in approximations that went beyond the QRPA order, e. g. [66][67][68]. Single-particle energies were usually obtained from the Nilsson potential, with slight shifts to improve phenomenology, and the strength of the QQ interactions was modified slightly from the self-consistent value so as to reproduce the energies of the γ-vibrational states.…”

Algebraic Collective Model Description of 166Er

“…These states and their anharmonicities are of a great interest since they provide a stringent test of nuclear models. For example, the Quasiphonon Nuclear Model predicts no K = 0 + double-γ vibrations below 2.5 MeV in 166 Er [10]. A study of double-γ vibrations using the intrinsic-state formalism of the Interacting Boson Model (IBM) has revealed that large anharmonicities can only be obtained for a finite number of bosons combined with a three-body term in the Hamiltonian that can induce triaxiality [11].…”