相关论文: A Novel Nuclear Model for Double Beta Decay
A version of the pn-continuum-QRPA is outlined and applied to describe the Gamow-Teller strength distributions for $\beta\beta$-decaying open-shell nuclei. The calculation results obtained for the pairs of nuclei $^{116}$Cd-Sn and…
$^{48}$Ca, the lightest double beta decay candidate, is the only one simple enough to be treated exactly in the nuclear shell model. Thus, the $\beta\beta(2\nu)$ half-life measurement, reported here, provides a unique test of the nuclear…
We explore the relation between the nuclear matrix elements of neutrinoless double-beta ($0\nu\beta\beta$) decay and two other processes: double Gamow-Teller (DGT) and double-magnetic dipole (M1M1) transitions, with focus on medium-mass to…
Nuclear matrix elements (NMEs) for two neutrino double beta decays are discussed in terms of the Fermi Surface Quasi-Particle (FSQP) Model. The evaluated NMEs agree with the observed NMEs . The new NMEs for two neutrino double beta decays…
The recently proposed Fully-Renormalized QRPA (FR-QRPA), which fullfils the Ikeda sum rule (ISR) exactly, is applied to the two-neutrino double beta decay of $^{76}$Ge, $^{82}$Se, $^{100}$Mo, $^{116}$Cd, $^{128}$Te and $^{130}$Xe. The…
$\beta$-decay properties of nuclei are investigated within the relativistic nuclear energy density functional framework by varying the temperature and density, conditions relevant to the final stages of stellar evolution. Both thermal and…
A new theoretical approach to spin-isospin excitations in open-shell nuclei is presented. The developed method is based on the relativistic meson-exchange nuclear Lagrangian of Quantum Hadrodynamics and extends the response theory for…
Nuclear $\beta$ decay is a key element of the astrophysical rapid neutron capture process ($r$-process). In this paper, we present state-of-the-art global $\beta$-decay calculations based on the quantified relativistic nuclear energy…
An approach to pairing in finite nuclei at nonzero temperature is proposed, which incorporates the effects due to the quasiparticle-number fluctuation (QNF) around Bardeen-Cooper-Schrieffer (BCS) mean field and dynamic coupling to…
We use a solvable model to examine double-beta decay, focusing on the neutrinoless mode. After examining the ways in which the neutrino propagator affects the corresponding matrix element, we address the problem of finite model-space size…
A modern chiral potential incorporating the three-body force is adopted to investigate bulk properties, spectra, and nuclear responses of closed-(sub)shell nuclei throughout the nuclear chart within a particle-hole (p-h) renormalized…
The simultaneous emission of two $\alpha$ particles--double-$\alpha$ decay--represents a long-predicted but unobserved mode of nuclear radioactivity. Here we formulate this process as a genuine three-body problem within the hyperspherical…
We describe a new implementation of the quasiparticle random phase approximation (QRPA) in axially-symmetric deformed nuclei with Skyrme and volume-pairing energy-density functionals. After using a variety of tests to demonstrate the…
In nuclear $\beta$-decay calculations, the axial-vector coupling constant $g_A \approx 1.27$ usually needs to be quenched phenomenologically by a factor $q~\approx$ 0.75 to reproduce {the Gamow-Teller (GT) transition strengths}. We propose…
We report microscopic calculation of key $\beta$-decay properties for some of the crucial waiting point species having neutron closed magic shells 50 and 82. Our calculation bear astrophysical significance vis-\'{a}-vis speeding of the…
A new Quasiparticle Random Phase Approximation approach is presented. The corresponding ground state is variationally determined and exhibits a minimum energy. New solutions for the ground state, some with spontaneously broken symmetry, of…
We develop the formalism for calculating the decay rate of neutrinoless double beta decay to the $2^+$ excited states within L-R symmetric model. We consider the effects from induced hadronic currents up to NLO. The QRPA method in a…
We test the effects of an approximate treatment of two-body contributions to the axial-vector current on the QRPA matrix elements for neutrinoless double-beta decay in a range of isotopes. The form and strength of the two-body terms come…
The primary computational challenge when simulating nonadiabatic ab initio molecular dynamics is the unfavorable compute costs of electronic structure calculations with molecular size. Simple electronic structure theories, like…
Study of the neutrinoless $\beta\beta$ decay allows us to put a stringent limit on the effective neutrino Majorana mass, a quantity of fundamental importance. To test our ability to evaluate the nuclear matrix elements that govern the decay…