Predictions of α-decay half-lives for neutron-deficient nuclei with the aid of artificial neural network

关于 QRPA 形式体系内 β 衰变半衰期计算中配对关联作用的研究

On the role of pairing correlations in calculation of \b{eta}-decay half-lives within QRPA formalism

本文利用含多壳层变形空间和示意相互作用的 pn-QRPA 模型，研究配对间隙及质子-中子剩余相互作用对中等质量缺中子核 β+/EC 半衰期的影响，提升了与实验数据的符合度。

Hg、Pb和Po同位素中β衰变的重新研究

Re examination of \b{eta} decay in Hg, Pb and Po Isotopes

本研究重新考察核形变对缺中子Hg、Pb、Po同位素GT强度分布的影响，通过相对论平均场模型和形变质子-中子准无规相位近似模型计算，发现半衰期和GT强度分布随形状参数变化显著。

探索α衰变与质子放射性之间的竞争：邻近势形式体系的比较研究

Exploring the competition between $α$-decay and proton radioactivity: A comparative study of proximity potential formalisms

本文系统比较了不同邻近势形式体系下缺中子核的质子放射性与α衰变竞争，并引入热效应，发现质子放射性在质子滴线附近核素中占主导，同时建立了半衰期与穿透概率的普适关联曲线。

Effects of deformation on the beta-decay patterns of light even-even and odd-mass Hg and Pt isotopes

Bulk and decay properties, including deformation energy curves, charge mean square radii, Gamow-Teller (GT) strength distributions, and beta-decay half-lives, are studied in neutron-deficient even-even and odd-A Hg and Pt isotopes. The nuclear structure is described microscopically from deformed quasiparticle random-phase approximation calculations with residual interactions in both particle-hole and particle-particle channels, performed on top of a self-consistent deformed quasiparticle Skyrme Hartree-Fock basis. The observed sensitivity of the, not yet measured, GT strength distributions to …

Weak interaction rates for Kr and Sr waiting-point nuclei under rp-process conditions

Weak interaction rates are studied in neutron deficient Kr and Sr waiting-point isotopes in ranges of densities and temperatures relevant for the rp-process. The nuclear structure is described within a microscopic model (deformed QRPA) that reproduces not only the half-lives but also the Gamow-Teller strength distributions recently measured. The various sensitivities of the decay rates to both density and temperature are discussed. Continuum electron capture is shown to contribute significantly to the weak rates at rp-process conditions.

自发单质子放射性的半衰期理论计算

Theoretical calculations on half-lives of spontaneous one-proton radioactivity

利用变形Woods-Saxon势、自旋-轨道势和扩展库仑势构建子核-质子势，基于量子隧穿模型和微观Gamow态理论系统计算了各种质子发射体的半衰期，并预测了fpg壳层以下可能更轻的质子发射体的半衰期。

Nuclear $β^+$/EC decays in covariant density functional theory and the impact of isoscalar proton-neutron pairing

Self-consistent proton-neutron quasiparticle random phase approximation based on the spherical nonlinear point-coupling relativistic Hartree-Bogoliubov theory is established and used to investigate the $β^+$/EC-decay half-lives of neutron-deficient Ar, Ca, Ti, Fe, Ni, Zn, Cd, and Sn isotopes. The isoscalar proton-neutron pairing is found to play an important role in reducing the decay half-lives, which is consistent with the same mechanism in the $β$ decays of neutron-rich nuclei. The experimental $β^+$/EC-decay half-lives can be well reproduced by a universal isoscalar proton-neutron pairing …

Superheavies: Theoretical incitements and predictions

It is well known that in fusion reactions one may get only neutron deficient superheavy nuclei located far from the island of stability. The multi-nucleon transfer reactions allow one to produce more neutron enriched new heavy nuclei but the corresponding cross sections are rather low. Neutron capture process is considered here as alternative method for production of long-lived neutron rich superheavy nuclei. Strong neutron fluxes might be provided by nuclear reactors and nuclear explosions in laboratory frame and by supernova explosions in nature. All these cases are discussed in the paper.

$β$-decay half-lives and nuclear structure of exotic proton-rich waiting point nuclei under $rp$-process conditions

We investigate even-even nuclei in the $A\sim70$ mass region within the framework of the proton-neutron quasi-particle random phase approximation (\mbox{pn-QRPA}) and the interacting boson model-1 (\mbox{IBM-1}). Our work includes calculation of the energy spectra and the potential energy surfaces $V(β,γ)$ of Zn, Ge, Se, Kr and Sr nuclei with the same proton and neutron number, $N = Z$. The parametrization of the \mbox{IBM-1} Hamiltonian was performed for the calculation of the energy levels in the ground state bands. Geometric shape of the nuclei was predicted by plotting the potential energy…

Microscopic mechanism of charged-particle radioactivity and generalization of the Geiger-Nuttall law

A linear relation for charged-particle emissions is presented starting from the microscopic mechanism of the radioactive decay. It relates the logarithms of the decay half-lives with two variables, called $χ'$ and $ρ'$, which depend upon the $Q$-values of the outgoing clusters as well as the masses and charges of the nuclei involved in the decay. This relation explains well all known cluster decays. It is found to be a generalization of the Geiger-Nuttall law in $α$ radioactivity and therefore we call it the universal decay law. Predictions on the most likely emissions of various clusters are …

Evolution of E2 transition strength in deformed hafnium isotopes from new measurements on $^{172}$Hf, $^{174}$Hf, and $^{176}$Hf

The available data for E2 transition strengths in the region between neutron-deficient Hf and Pt isotopes are far from complete. More and precise data are needed to enhance the picture of structure evolution in this region and to test state-of-the-art nuclear models. In a simple model, the maximum collectivity is expected at the middle of the major shell. However, for actual nuclei, this picture may no longer be the case, and one should use a more realistic nuclear-structure model. We address this point by studying the spectroscopy of Hf. We remeasure the 2^+_1 half-lives of 172,174,176Hf, for…

rp-Process weak-interaction mediated rates of waiting-point nuclei

Electron capture and positron decay rates are calculated for neutron-deficient Kr and Sr waiting point nuclei in stellar matter. The calculation is performed within the framework of pn-QRPA model for rp-process conditions. Fine tuning of particle-particle, particle-hole interaction parameters and a proper choice of the deformation parameter resulted in an accurate reproduction of the measured half-lives. The same model parameters were used to calculate stellar rates. Inclusion of measured Gamow-Teller strength distributions finally led to a reliable calculation of weak rates that reproduced th…

由 $r$-过程种子产生 $p$-核：$νr$-过程

Production of $p$-nuclei from $r$-process seeds: the $νr$-process

本文提出 $νr$-过程：在强中微子通量下，富中子抛射物中的 $r$-过程种子经快速中微子吸收越过 β 稳定线生成 $p$-核，并分析其天体物理条件。