Low-lying dipole response in the Relativistic Quasiparticle Time Blocking Approximation and its influence on neutron capture cross sections

Abstract

We have computed dipole strength distributions for nickel and tin isotopes within the Relativistic Quasiparticle Time Blocking approximation (RQTBA). These calculations provide a good description of data, including the neutron-rich tin isotopes ${}^{130,132}$Sn. The resulting dipole strengths have been implemented in Hauser-Feshbach calculations of astrophysical neutron capture rates relevant for r-process nucleosynthesis studies. The RQTBA calculations show the presence of enhanced dipole strength at energies around the neutron threshold for neutron rich nuclei. The computed neutron capture rates are sensitive to the fine structure of the low lying dipole strength, which emphasizes the importance of a reliable knowledge of this excitation mode.

15 pages, 4 figures, Accepted in Nucl. Phys. A

References in corpus (14)

• A New Parameterization for the Lagrangian Density of Relativistic Mean Field Theory
• Astrophysical Reaction Rates From Statistical Model Calculations
• Shell-model calculations of stellar weak interaction rates: II. Weak rates for nuclei in the mass range A=45-65 in supernovae environment
• Exotic modes of excitation in atomic nuclei far from stability
• Nuclear Level Density and the Determination of Thermonuclear Rates for Astrophysics
• Microscopic HFB+QRPA predictions of dipole strength for astrophysics applications
• Large-scale QRPA calculation of E1-strength and its impact on the neutron capture cross section
• Quasiparticle random phase approximation based on the relativistic Hartree-Bogoliubov model
• Investigation of Pygmy Dipole Resonances in the Tin Region
• Relativistic quasiparticle time blocking approximation. Dipole response of open-shell nuclei
• Relativistic quasiparticle time blocking approximation. II. Pygmy dipole resonance in neutron-rich nuclei
• Large-scale prediction of the parity distribution in the nuclear level density and application to astrophysical reaction rates
• Astrophysical relevance of $\gamma$ transition energies
• Complete inclusion of parity-dependent level densities in the statistical description of astrophysical reaction rates

Cited by in corpus (47)

• Origin of the Heaviest Elements: the Rapid Neutron-Capture Process
• The impact of individual nuclear properties on $r$-process nucleosynthesis
• Nuclear Equation of State from ground and collective excited state properties of nuclei
• Dynamical r-process studies within the neutrino-driven wind scenario and its sensitivity to the nuclear physics input
• The Path to Improved Reaction Rates for Astrophysics
• Large-scale Continuum Random Phase Approximation predictions of dipole strength for astrophysical applications
• Have Superheavy Elements been Produced in Nature?
• Low-energy electric dipole response in 120Sn
• Novel Techniques for Constraining Neutron-Capture Rates Relevant for r-Process Heavy-Element Nucleosynthesis
• Low-energy limit of the radiative dipole strength in nuclei
• Low-energy dipole strength in 112,120Sn
• Population of dipole states via isoscalar probes: the splitting of pygmy dipole resonance in ${}^{124}$Sn}
• Electric and magnetic dipole modes in high-resolution inelastic proton scattering at $0^{\circ }$
• Nuclear response theory for spin-isospin excitations in a relativistic quasiparticle-phonon coupling framework
• Self-consistent calculations of the strength function and radiative neutron capture cross section for stable and unstable tin isotopes
• Relativistic two-phonon model for low-energy nuclear response
• Test of the Brink-Axel hypothesis for the pygmy dipole resonance
• Low-energy multipole response in nuclei at finite temperature
• Electric and magnetic dipole strength in 112,114,116,118,120,124Sn
• Electric dipole response of neutron-rich Calcium isotopes in relativistic quasiparticle time blocking approximation
• Toward an accurate strongly-coupled many-body theory within the equation of motion framework
• Neutrino-pair emission from nuclear de-excitation in core-collapse supernova simulations
• Finite-temperature relativistic nuclear field theory: an application to the dipole response
• Accessing the Single-Particle Structure of the Pygmy Dipole Resonance in ${}^{208}$Pb
• Temperature dependence of nuclear spin-isospin response and beta decay in hot astrophysical environments
• Multipole excitations in hot nuclei within the finite temperature quasiparticle random phase approximation framework
• Nuclear Dipole Response in the Finite-Temperature Relativistic Time Blocking Approximation
• Gamma strength function and level density of ${}^{208}$Pb from forward-angle proton scattering at 295 MeV
• Continuum quasiparticle random phase approximation for astrophysical direct neutron capture reaction of neutron-rich nuclei
• Dipole response in neutron-rich nuclei with new Skyrme interactions
• Structure and decay of the pygmy dipole resonance in 26Ne
• Low-energy quadrupole states in neutron-rich tin nuclei
• Beyond-mean-field effects on the symmetry energy and its slope from the low-lying dipole response of ${}^{68}$Ni
• Breaking of axial symmetry in excited heavy nuclei as identified in Giant Dipole Resonance data
• Nuclear response in a finite-temperature relativistic framework
• Nature of low-lying electric dipole resonance excitations in 74Ge
• Damping of the isovector giant dipole resonance in ${}^{40,48}$Ca
• Nuclear excitations within microscopic EDF approaches : pairing and temperature effects on the dipole response
• Experimental study of excited states of ${}^{62}$Ni via one-neutron $(d,p)$ transfer up to the neutron-separation threshold and characteristics of the pygmy dipole resonance states
• Astrophysical Rates for Explosive Nucleosynthesis: Stellar and Laboratory Rates for Exotic Nuclei
• Instantaneous Shape Sampling - a model for the $\gamma$-absorption cross section of transitional nuclei
• Continuum random-phase approximation for (n,γ) reactions on neutron-rich nuclei: collective effects and resonances
• Theory of nuclear collective vibrations
• Nuclear Reactions in Evolving Stars
• Quasiparticle-vibration coupling effects on nuclear transitions of astrophysical interest
• Isospin dynamics in nuclear structure
• Comprehensive test of the Brink-Axel hypothesis in the energy region of the pygmy dipole resonance