Related papers: Quadrupole-quadrupole interaction calculations whi…
We extend the ab initio coupled-cluster effective interaction (CCEI) method to deformed open-shell nuclei with protons and neutrons in the valence space, and compute binding energies and excited states of isotopes of neon and magnesium. We…
We present an approach to derive effective shell-model interactions from microscopic nuclear forces. The similarity-transformed coupled-cluster Hamiltonian decouples the single-reference state of a closed-shell nucleus and provides us with…
A Hubbard-like model with SU(4) symmetry for electrons with two-fold orbital degeneracy is studied extensively. Exact solution in one dimension is derived by means of Bethe ansatz, where the sites are supposed to be occupied by at most two…
We present a systematic study of the $^{10-14}\text{C}$ isotopes within the \textit{ab initio} no-core shell model theory. We apply four different realistic nucleon-nucleon (NN) interactions: (i) the charge-dependent Bonn 2000 (CDB2K)…
Shell-model calculations for several mass 16-19 nuclei are performed using the N$^3$LO two-nucleon potential $V_{2N}$ with and without the addition of an in-medium three-nucleon potential $V_{3N}^{med}$, which is a density-dependent…
We report on the experimental study of quadrupole collectivity in the neutron-deficient nucleus \nuc{104}{Sn} using intermediate-energy Coulomb excitation. The $B(E2; 0^+_1 \rightarrow 2^+_1)$ value for the excitation of the first $2^+$…
We have studied the low lying magnetic spectra of 12C, 16O, 40Ca, 48Ca and 208Pb nuclei within the Random Phase Approximation (RPA) theory, finding that the description of low-lying magnetic states of doubly-closed-shell nuclei imposes…
We present our results on properties of ground states for nucleonic systems in the presence of random two-body interactions. In particular we present probability distributions for parity, seniority, spectroscopic (i.e., in the laboratory…
Octupole correlations in the low-energy collective states of neutron-rich nuclei with the neutron number $N\approx56$ are studied within the interacting boson model (IBM) that is based on the nuclear density functional theory. The…
We find that the excitation energies of single analog states for odd-even nuclei in the f$_{7/2}$ shell with J=j=7/2$^{-}$ and the J=0$^{+}$ double analog states in the even-even nuclei are well described by the formulas $E^{*}(j,T+1) = b…
Large scale shell model calculations, with dimensions reaching 10**9, are carried out to describe the recently observed deformed (ND) and superdeformed (SD) bands based on the first and second excited 0+ states of 40-Ca at 3.35-MeV and…
Transition charge density (TCD) for $ 0^+\to 2_1^+ $ excitation have been calculated for $\rm ^{70,72,74,76}Ge$ nuclei within microscopic variational framework employing $2p_{3/2}, 1f_{5/2}, 2p_{1/2}$ and $1g_{9/2}$ valence space. The…
We study the robustness of topological ground state degeneracy to long-range interactions in quantum many-body systems. We focus on slowly decaying two-body interactions that scale like a power-law $1/r^\alpha$ where $\alpha$ is smaller…
The low energy excited $0_{2,3}^+$ states in $^{96}$Sr are amongst the most prominent examples of shape coexistence across the nuclear landscape. In this work, the neutron $[2s_{1/2}]^2$ content of the $0_{1,2,3}^+$ states in $^{96}$Sr was…
Shell model calculations have been performed for the nucleus 94Mo. The calculated excitation energies and electromagnetic properties of low-lying states are in good agreement with the data, which include states with mixed-symmetry (MS)…
We define the "quadrupole ratio" r_{Q}=\dfrac{Q_{0}(S)}{Q_{0}(B)} where Q_{0}(S) is the intrinsic quadrupole moment obtained from the static quadrupole moment of the 2_{1}^{+} state of an even-even nucleus and Q_{0}(B) the intrinsic…
We point out a simplicity that arises when we use an interaction in which only an energy with odd J is non-zero. The emphasis is on J= J_{max} and in particular J=9+ in the g_{9/2} shell. It is noted that high overlaps can be deceptive. In…
A system consisting of two neutral spin 1/2 particles is analyzed for two magnetic field perturbations: 1) an inhomogeneous magnetic field over all space, and 2) external fields over a half space containing only one of the particles. The…
The model, introduced in a previous paper, for the description of the octupole and quadrupole degrees of freedom in conditions close to the axial symmetry, is applied to situations of shape phase transitions where the quadrupole amplitude…
With nucleons occupying an oscillator shell $\eta$, there are $2^{\eta/2}$ number of $SU(3)$ algebras; $\eta/2$ is the integer part of $\eta/2$. Analyzing the first non trivial situation with four $SU(3)$ algebras in $(sdg)$ space,…