相关论文: Anomaly in first-forbidden transitions of $^{176}$…
Mainly because of its long half-life and despite its scientific relevance, spectroscopic measurements of $^{176}$Lu forbidden $\beta$-decays are very limited and lack formulation of shape factors. A direct precise measurement of its $Q$…
R-process nucleosynthesis models rely, by necessity, on nuclear structure models for input. Particularly important are beta-decay half-lives of neutron rich nuclei. At present only a single systematic calculation exists that provides values…
In astrophysical environments, the long-lived (\T_1/2 = 37.6 Gy) ground state of 176-Lu can communicate with a short-lived (T_1/2 = 3.664 h) isomeric level through thermal excitations. Thus, the lifetime of 176-Lu in an astrophysical…
$\beta$-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…
Nuclei with magic numbers serve as important benchmarks in nuclear theory. In addition, neutron-rich nuclei play an important role in the astrophysical rapid neutron-capture process (r-process). 78Ni is the only doubly-magic nucleus that is…
First-forbidden (FF) transitions can play an important role in decreasing the calculated half-lives specially in environments where allowed Gamow-Teller (GT) transitions are unfavored. Of special mention is the case of neutron-rich nuclei…
We investigated the effects of first-forbidden transitions in $\beta$ decays on the production of the r-process $A \sim 195$ peak. The theoretical calculated $\beta$-decay rates with $\beta$-delayed neutron emission were examined using…
Accurate transition probabilities for forbidden lines are important diagnostic parameters for low-density astrophysical plasmas. In this paper we present experimental atomic data for forbidden [FeII] transitions that are observed as strong…
We have performed large-scale shell-model calculations of the half-lives and neutron-branching probabilities of the r-process waiting point nuclei at the magic neutron numbers N=50, 82, and 126. The calculations include contributions from…
Some nuclear reaction channels may not be easily identified, but they can still contribute to very important characteristics like nuclear reaction cross-sections, isomeric yields, etc. The dineutron, as a bound nucleus of two neutrons, can…
In astrophysical environments, allowed Gamow-Teller (GT) transitions are important, particularly for $\beta$-decay rates in presupernova evolution of massive stars, since they contribute to the fine-tuning of the lepton-to-baryon content of…
Recent discussions about the origin of the Gallium Anomaly have motivated a remeasurement of the half life of $^{71}$Ge. We have conducted three separate measurements using dedicated planar Ge detectors: one with $^{55}$Fe as a standard,…
In the present work, we have predicted the half-lives for the $\beta^{-}$ decay for higher forbidden unique transitions in the mass range of nuclei from A = 40-138. For these transitions, the experimental data for half-lives are not…
We propose a theoretical method to calculate the stellar $\beta$-decay rates of nuclei in stellar environments with high temperature and density, based on the projected shell model, where contributions from both allowed and first-forbidden…
Constraints on the lifetime of the heavy sterile neutrino, that was proposed as a possible interpretation of the KARMEN anomaly, are derived from primordial nucleosynthesis and SN 1987A. Together with the recent experimental bounds on the…
Data from the Sudbury Neutrino Observatory have been used to constrain the lifetime for nucleon decay to ``invisible'' modes, such as n -> 3 nu. The analysis was based on a search for gamma-rays from the de-excitation of the residual…
$\beta$-decay rates play a decisive role in understanding the nucleosynthesis of heavy elements and are governed by microscopic nuclear-structure information. A sudden shortening of the half-lives of Ni isotopes beyond $N=50$ was observed…
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…
Anomalous transitions involving photons derived by many-body interaction of the form, $\partial_{\mu} G^{\mu}$, in the standard model are studied. This does not affect the equation of motion in the bulk, but makes wave functions modified,…
The K-electron capture half-life of $^{123}$Te has been recently measured to be $t^K_{exp}=2.4\times 10^{19}$ yr, and constitutes the longest half-life ever measured in a single $\beta$-transition of any nuclear species. We have calculated…