Related papers: $\beta$-decay of key titanium isotopes in stellar …
In the first stage of this work, we perform detailed calculations for the cross sections of the electron capture on nuclei under laboratory conditions. Towards this aim we exploit the advantages of a refined version of the proton-neutron…
Gamow-Teller transitions in isotopes of chromium play a consequential role in the presupernova evolution of massive stars. $\beta$-decay and electron capture rates on chromium isotopes significantly affect the time rate of change of lepton…
The neutrino cooling and gamma heating rates are considered as an important input needed to study the final phases of the evolution of high-mass stars. The weak-interaction mediated processes, namely the $\beta$-decay and electron capture,…
The electron screening strong effect on the electron energy and threshold energy of the beta decay reaction. in this paper, we study the $\beta^-$ decay rates of some iron isotopes. The electron screening beta decay rates increase by about…
Improved values for stellar weak interaction rates have been recently calculated based upon a large shell model diagonalization. Using these new rates (for both beta decay and electron capture), we have examined the presupernova evolution…
Based on large-scale shell model calculations we have determined the electron capture, positron capture and beta-decay rates on more than 100 nuclei in the mass range A=45-65. The rates are given for densities \rho Y_e =10^7-10^{10}…
Beta-decay properties of neutron-rich Ca, Ti, and Cr isotopes are studied within a deformed proton-neutron quasiparticle random-phase approximation. The underlying mean field is described self-consistently from deformed Skyrme Hartree-Fock…
The allowed charge-changing transitions are the most common weak interaction processes of spin-isospin form that play a crucial role in several nuclear/astrophysical processes. The first-forbidden (FF) transition becomes important, in the…
Recent shell-model calculations of weak-interaction rates for nuclei in the mass range A = 45 - 65 have resulted in substantial revisions to the hitherto standard set of Fuller, Fowler, & Newman (FFN). In particular, key electron-capture…
A detailed model for the calculation of beta decay rates of the $fp$ shell nuclei for situations prevailing in pre-supernova and collapse phases of evolution of the core of massive stars leading to supernova explosion has been extended for…
We present a new calculation of neutrino emissivities and energy spectra from a massive star going through the advanced stages of nuclear burning (presupernova) in the months before becoming a supernova. The contributions from beta decay…
Weak decay rates under stellar density and temperature conditions holding at the rapid proton capture process are studied in neutron-deficient medium-mass waiting point nuclei extending from Ni up to Sn. Neighboring isotopes to these…
We study two-neutrino ($2\nu\beta\beta$) and neutrinoless double-$\beta$ ($0\nu\beta\beta$) decays in the nuclear shell model and proton-neutron quasiparticle random-phase approximation (pnQRPA) frameworks. Calculating the decay half-life…
Isotopes with low-lying long-lived isomers can behave very differently from other isotopes in astrophysical environments. In particular, the assumption of thermal equilibrium in computing the temperature-dependent $\beta$-decay rates of…
In this paper we show that the proton-neutron residual interaction can play an important role in the reliability of calculated $\beta$-decay half-lives. It may also improve the prediction power of the quasiparticle random phase…
Due to its abundance and its relatively high capture rates, $^{55}$Co is one of the key nuclide that can control the dynamics of core collapse of a massive star. Previously we introduced our microscopic calculations of capture rates on…
Reliable and precise knowledge of the $\beta$-decay properties of neutron-rich nuclei is important for a better understanding of the $r$-process. We report the computation of $\beta$-decay properties of neutron-rich Cerium isotopes…
The $\beta$-decay half-lives of neutron-rich nuclei with $20 \leqslant Z \leqslant 50$ are systematically investigated using the newly developed fully self-consistent proton-neutron quasiparticle random phase approximation (QRPA), based on…
During the late stages of gravitational core-collapse of massive stars, extreme isospin asymmetries are reached within the core. Due to the lack of microscopic calculations of electron capture (EC) rates for all relevant nuclei, in general…
We present a new theory describing the variation of electron capture and bound-state $\beta$-decays in atomic ions and (non) local thermodynamic equilibrium ((N)LTE) plasmas. We adopt the Takahashi-Yokoi nuclear model with added corrections…