Related papers: Study of $\beta^+$/EC-decay properties of $sd$ she…
We have calculated the Gamow-Teller matrix elements of 64 decays of nuclei in the mass range A=41--50. In all the cases the valence space of the full pf-shell is used. Agreement with the experimental results demands the introduction of an…
We present the nuclear matrix element for the neutrinoless double-beta decay of $^{48}$Ca based on large-scale shell-model calculations including two harmonic oscillator shells ($sd$ and $pf$ shells). The excitation spectra of $^{48}$Ca 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…
The prediction of nuclear half-lives is vital for understanding nuclear stability with significant applications in astrophysics, nuclear energy, and medical physics. This study investigates the $\alpha$-decay half-lives of 154 actinide…
Most uncertainties regarding the theoretical study of the neutrinoless double-beta decay are related to the accuracy of the nuclear matrix elements that appear in the expressions of the lifetimes. We calculate the nuclear matrix elements…
We examine the effect of nuclear deformation on the calculated $\beta$-decay half-lives of 55 neutron-rich nuclei. The deformation values were computed using DD-PC1 and DD-ME2 interactions in the Relativistic Hartree-Bogoliubov model. Yet…
We discuss two conditions needed for correct computation of $2\nu \beta\beta$ nuclear matrix-elements within the realistic shell-model framework. An algorithm in which intermediate states are treated based on Whitehead's moment method is…
We investigate the effect of pairing correlations on the computed Gamow-Teller (GT) strength distributions and corresponding $\beta$-decay half-lives. The calculations are performed for a total of 47 sd-shell nuclei, for $20 < A < 30$,…
Neutrinoless double beta decay searches are currently among the major foci of experimental physics. The observation of such a decay will have important implications in our understanding of the intrinsic nature of neutrinos and shed light on…
A new evaluation of 2beta-decay half lives and their systematics is presented. These data extend the previous evaluation and include the analysis of all recent measurements. The nuclear matrix elements for 2beta-decay transitions in 12…
The renormalization of the weak charge-changing hadronic current as a function of the reaction energy release is studied at the nucleonic level. We have calculated the average quenching factors for each type of current (vector, axial vector…
Nuclear double $\beta$-decay with two neutrinos is a rare and important process for natural radioactivity of unstable nuclei. The experimental data of nuclear double $\beta^{-}$-decay with two neutrinos are analyzed and a systematic law to…
Half-lives $T_{1/2}^{2\nu}$ for two neutrino positron double beta decay modes $\beta^{+}$EC/ECEC are calculated for $^{84}$Sr, a nucleus of current experimental interest, within the framework of the deformed shell model based on…
$\beta$-decay rates of neutron-rich nuclei, in particular those located at neutron shell closures, play a central role in simulations of the heavy-element nucleosynthesis and resulting abundance distributions. We present $\beta$-decay…
Nuclear weak rates in stellar environments are obtained by shell-model calculations including Gamow-Teller (GT) and spin-dipole transitions, and applied to nuclear weak processes in stars. The important roles of accurate weak rates for the…
The nuclear shell model is one of the successful models in theoretical understanding of nuclear structure. If a convenient effective interaction can be found between nucleons, various observables such as energies of nuclear states are…
We reexamine the nuclear structure properties of waiting point nuclei around A70 using the interacting boson model 1 (IBM 1) and the relativistic mean field (RMF) model. Effective density dependent meson exchange functional (DD ME2) and…
Two-neutrino double-beta ($2\nu\beta\beta$) decay has been used to constrain the neutron-proton part of effective interactions, which in turn is used to compute the nuclear matrix elements for neutrinoless double-beta decay, the observation…
The $\beta$-decay half-lives of 55 neutron-rich nuclei $^{134-139}$Sn, $^{134-142}$Sb, $^{137-144}$Te, $^{140-146}$I, $^{142-148}$Xe, $^{145-151}$Cs, $^{148-153}$Ba, $^{151-155}$La were measured at the Radioactive Isotope Beam Factory…
$\beta$-decay half-lives of neutron-rich nuclei around $N=82$ are key data to understand the $r$-process nucleosynthesis. We performed large-scale shell-model calculations in this region using a newly constructed shell-model Hamiltonian,…