Reaching the limits of nuclear stability

Thoennessen, M.

doi:10.1088/0034-4885/67/7/r04

Cited by 167 publications

(199 citation statements)

References 248 publications

(447 reference statements)

Supporting

Mentioning

186

Contrasting

Unclassified

Order By: Relevance

“…Exploring the limit of nuclear binding has always been a priority in nuclear physics and investigating the properties of all nuclei in the nuclear landscape is crucial for understanding the nuclear force, and the formation of elements in astrophysics, etc. [1,2].…”

Section: Introductionmentioning

confidence: 99%

“…To date, the existence of about 3000 nuclides has been confirmed experimentally [1,2]. The proton-rich boundary of the nuclear territory has been experimentally determined up to protactinium [1,2].…”

Section: Introductionmentioning

confidence: 99%

“…The proton-rich boundary of the nuclear territory has been experimentally determined up to protactinium [1,2]. However, the neutron-rich boundary is known only up to oxygen [1,2], and most of the neutron-rich nuclei far from the valley of stability seem still beyond the experimental capability in the foreseeable future.…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

The limits of the nuclear landscape explored by the relativistic continuum Hartree–Bogoliubov theory

Xia

Lim

Zhao

et al. 2018

Atomic Data and Nuclear Data Tables

206

127

View full text Add to dashboard Cite

The ground-state properties of nuclei with 8 Z 120 from the proton drip line to the neutron drip line have been investigated using the spherical relativistic continuum Hartree-Bogoliubov (RCHB) theory with the relativistic density functional PC-PK1. With the effects of the continuum included, there are totally 9035 nuclei predicted to be bound, which largely extends the existing nuclear landscapes predicted with other methods. The calculated binding energies, separation energies, neutron and proton Fermi surfaces, root-mean-square (rms) radii of neutron, proton, matter, and charge distributions, ground-state spins and parities are tabulated. The extension of the nuclear landscape obtained with RCHB is discussed in detail, in particular for the neutron-rich side, in comparison with the relativistic mean field calculations without pairing correlations and also other predicted landscapes. It is found that the coupling between the bound states and the continuum due to the pairing correlations plays an essential role in extending the nuclear landscape.The systematics of the separation energies, radii, densities, potentials and pairing energies of the RCHB calculations are also discussed. In addition, the α-decay energies and proton emitters based on the RCHB calculations are investigated.

show abstract

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

The limits of the nuclear landscape explored by the relativistic continuum Hartree–Bogoliubov theory

Xia

Lim

Zhao

et al. 2018

Atomic Data and Nuclear Data Tables

206

127

View full text Add to dashboard Cite

show abstract

“…A number of recent advances in the synthesis of very heavy and superheavy elements (SHE) [1,2] as well as highly neutron deficient medium mass nuclei [3], have spurred theoretical investigations into the decay modes and masses of these nuclei. These investigations aim to test and advance ideas on the extant nuclear structure for heavy and high Coulomb repulsive force containing nuclei.…”

Section: Introductionmentioning

confidence: 99%

The generalized liquid drop model alpha-decay formula: Predictability analysis and superheavy element alpha half-lives

Dasgupta‐Schubert

Reyes²

2007

Atomic Data and Nuclear Data Tables

View full text Add to dashboard Cite

The predictive accuracy of the generalized liquid drop model (GLDM) formula for alpha decay half-lives has been investigated in a detailed manner and a variant of the formula with improved coefficients is proposed. The method employs the experimental alpha half-lives of the well-known alpha standards (REFERENCE) to obtain the coefficients of the analytical formula using the experimental Q α values (the DSR-E formula), as well as the finite range droplet model (FRDM) derived Q α values (the FRDM-FRDM formula). The predictive accuracy of these formulae were checked against the experimental alpha half-lives of an independent set of nuclei (TEST) that span approximately the same Z,A region as the standards and possess reliable alpha spectroscopic data, and were found to yield good results for the DSR-E formula but not for the FRDM-FRDM formula. The two formulae were used to obtain the alpha half-lives of super-heavy (SHE) and heavy nuclides where the relative accuracy was found to markedly improve for the FRDM-FRDM, which corroborates the appropriateness of the FRDM masses and the GLDM prescription for high Z,A nuclides. Further improvement resulted, especially for the FRDM-FRDM formula, after a simple linear optimization over the calculated and experimental half-lives of TEST was used to re-calculate the half-lives of the SHE and heavy nuclides. The advantage of this optimization was that it required no recalculation of the coefficients of the basic DSR-E or FRDM-FRDM formulae. The halflives for 324 medium-mass to super-heavy alpha decaying nuclides, calculated using these formulae and the comparison with experimental half-lives, are presented. Often the main and sometimes the only decay mode of these nuclei is alpha decay.For the SHE, the product nuclides of hot-fusion heavy ion reactions closest to the shell model predicted Island of Stability, decay by the emission of alpha particles. Chains of successive alpha decays are terminated by spontaneous fission as the shell-stabilized region is left behind [5,2].Thus identifying and characterizing the alpha decay sequences form a crucial part of the identification of SHE. Theoretically the mechanism is described by quantum mechanical tunneling through the potential energy barrier leading from the mother nucleus to the daughter nucleus and alpha particle. Consequently the predicted half-lives remain very sensitive to the shape and energetics of the barrier which as such, serve to test the particular theoretical model of the potential energy surfaces of these exotic nuclei. Various theoretical prescriptions since 1930 [6] have been proposed. Some of these as well as some empirical observations have been reduced to analytical formulae [7][8][9][10][11][12] that connect Q α , and the Z,A of the parent nuclide and wherein coefficients are typically obtained from fits to known alpha half-lives. The underlying model's description of the potential barrier lies implicit in the formula's functional form and its coefficients and this in part determines the merit of the formula....

show abstract

“…The structure and properties of barely stable nuclei at the limits of stability, have been demonstrated to deviate dramatically from the established patterns for ordinary and stable nuclei, see Ref. [1] and references therein for a recent review. One of the striking features of nuclei close to the drip line is the adjustment of shell gaps, giving rise to different magic numbers [2].…”

mentioning

confidence: 99%

Closed-shell properties ofO24withab initiocoupled-cluster theory

et al. 2011

View full text Add to dashboard Cite

We present a microscopic calculation of spectroscopic factors for neutron and proton removal from 24 O using the coupled-cluster method and a state-of-the-art chiral nucleon-nucleon interaction at next-to-next-to-next-to-leading order. In order to account for the coupling to the scattering continuum we use a Berggren single-particle basis that treats bound, resonant, and continuum states on an equal footing. We report neutron removal spectroscopic factors for the 23 O states J π = 1/2 + , 5/2 + , 3/2 − and 1/2 − , and proton removal spectroscopic factors for the 23 N states 1/2 − and 3/2 − . Our calculations support the accumulated experimental evidence that 24 O is a closed-shell nucleus.PACS numbers: 21.10.Jx, 21.60. De, 21.10.Pc, 31.15.bw, 24.10.Cn Introduction The study of nuclei far from stability is a leading direction in nuclear physics, experimentally and theoretically. It represents a considerable intellectual challenge to our understanding of the stability of matter itself, with potential implications for the synthesis of elements. An important aspect of this research direction is to understand how magic numbers and shells appear and evolve with increasing numbers of neutrons or protons. The structure and properties of barely stable nuclei at the limits of stability, have been demonstrated to deviate dramatically from the established patterns for ordinary and stable nuclei, see Ref.[1] and references therein for a recent review. One of the striking features of nuclei close to the drip line is the adjustment of shell gaps, giving rise to different magic numbers [2]. The way shell closures and single-particle properties evolve as functions of the number of nucleons forms one of the greatest challenges to our understanding of the basic features of nuclei, and thereby the stability of matter.The chain of oxygen isotopes up to 28 O is particularly interesting since these are the heaviest nuclei for which the drip line is well established. Two out of four stable even-even isotopes exhibit a doubly magic nature, namely 22 O (Z=8,N =14) and 24 O (Z=8, N =16). Several recent experiments [3-6] bring evidence that 24 O is the last stable oxygen isotope. This is remarkable, in particular if one considers the fact that the addition of a single proton on top of the Z = 8 closed shell brings the drip line of the fluorine isotopes to 31 F. Recent measurements [3] also suggest that 24 O has a spherical neutron configuration. The isotopes 25−28 O are all believed to be unstable towards neutron emission, even though 28 O is a doubly magic nucleus within the standard shell-model picture. This indicates that the magic number at the neutron drip line for the oxygen isotopes is not at N = 20 but rather at N = 16.Although spectroscopic factors are not observable quantities [9,10], they can be used to address shell closure properties within the context of a given model. Experimentally, spectroscopic factors are defined as the ratio of the observed reaction rate with respect to the same

show abstract

Reaching the limits of nuclear stability

Cited by 167 publications

References 248 publications

The limits of the nuclear landscape explored by the relativistic continuum Hartree–Bogoliubov theory

The limits of the nuclear landscape explored by the relativistic continuum Hartree–Bogoliubov theory

The generalized liquid drop model alpha-decay formula: Predictability analysis and superheavy element alpha half-lives

Closed-shell properties ofO24withab initiocoupled-cluster theory

Contact Info

Product

Resources

About