Related papers: Pygmy resonances and nucleosynthesis
The pygmy-dipole resonances and photon strength functions in stable and unstable Ni and Sn isotopes are calculated within the microscopic self-consistent version of the extended theory of finite fermi systems which includes the QRPA and…
A very important open question related to the pygmy dipole resonance is about its quite elusive collective nature. In this paper, within a harmonic oscillator shell model, generalizing an approach introduced by Brink, we first identify the…
A convergent method to extract the nuclear level density and the gamma-ray strength function from primary gamma-ray spectra has been established. Thermodynamical quantities have been obtained within the microcanonical and canonical ensemble…
A two-phonon version of the relativistic quasiparticle time blocking approximation (RQTBA-2) represents a new class of many-body models for nuclear structure calculations based on the covariant energy density functional. As a fully…
Low-energy dipole excitations have been investigated theoretically in N=50, several N=82 isotones and the Z=50 Sn isotopes. For this purpose a method incorporating both HFB and multi-phonon QPM theory is applied. A concentration of…
We study the effects of the phonon-phonon coupling on the low-energy electric dipole response within a microscopic model based on an effective Skyrme interaction. The finite rank separable approach for the quasiparticle random phase…
The pygmy dipole resonance (PDR), marked by enhanced electric dipole strength near particle emission energies, offers a unique perspective on the collective dynamics of nuclear structure. Its precise nature, particularly its degree of…
Dipole excitations below the neutron threshold in neutron rich Sn isotopes are studied theoretically in the Quasiparticle-Phonon Model with HFB single particle input. Of special interest are the low-lying two-phonon 1- states and the Pygmy…
The pygmy dipole resonance (PDR) is studied in various medium-heavy nuclei by using a Gogny interaction in a self-consistent Hartree-Fock plus Random Phase Approximation method. We compare the details of the PDR structure with those of the…
The E1 strength functions and radiative capture cross sections for several compound Sn isotopes, including unstable 132S n and 150S n, have been calculated using the self-consistent microscopic theory. In addition to the standard RPA or…
Starting from an effective Skyrme interaction we study effects of phonon-phonon coupling on the low-energy electric dipole response in $^{124-132}$Sn. The QRPA calculations are performed within a finite rank separable approximation. The…
We study a particular class of relativistic nuclear energy density functionals in which only nucleon degrees of freedom are explicitly used in the construction of effective interaction terms. Short-distance (high-momentum) correlations, as…
Background: Nuclear excited states within a wide range of excitation energies are formally described by the linear response theory. Besides its conventional formulation within the quasiparticle random phase approximation (QRPA) representing…
Reaction-rate calculations relevant to r-process nucleosynthesis depend sensitively on the nuclear $\gamma$-strength function ($\gamma$SF). Here we investigate the impact of low-lying pygmy dipole strength (PDS) in $(n,\gamma)$ and…
The electric quadrupole response in $^{112,114}$Sn isotopes is investigated by energy-density functional (EDF) and three-phonon quasiparticle-phonon model (QPM) theory with special emphasis on 2$^+$ excitations located above the first…
The electric dipole excitation of various nuclei is calculated with a Random Phase Approximation phenomenological approach. The evolution of the strength distribution in various groups of isotopes, oxygen, calcium, zirconium and tin, is…
Theoretical studies of low-lying dipole strength in even-even spherical nuclei within the relativistic quasiparticle time blocking approximation (RQTBA) are presented. The RQTBA developed recently as an extension of the self-consistent…
Some recent advancements of the nuclear many-body theory and selected results on nuclear giant and pygmy resonances are presented. The theory is compactly reviewed, with a special focus on the emergent scale of the quasiparticle-vibration…
A possible relation of the low-lying E1 (pygmy resonance) and toroidal strengths is analyzed by using Skyrme-RPA results for the strength functions, transition densities and current fields in $^{208}$Pb. It is shown that the irrotational…
We present recent investigations on dipole and quadrupole excitations in spherical skin nuclei, particular exploring their connection to the thickness of the neutron skin. Our theoretical method relies on density functional theory, which…