Related papers: Electron Capture Rates of Mid-fp Shell Nuclei for …
Using the theory of relativity in superstrong magnetic fields (SMFs) and nuclear shell model, we carry out estimation for electron capture (EC) rates on iron group nuclei in SMFs. The rates of change of electronic abundance (RCEA) due to EC…
A critical mass ONe core with a high ignition density is considered to end in gravitational collapse leading to neutron star formation. Being distinct from a Fe core collapse, the final evolution involves combustion flame propagation, in…
Nuclear electron capture rate from continuum in an astrophysical plasma environment (like solar core) is calculated using a modified Debye-Huckel screening potential and the related non-Gaussian q-distribution of electron momenta. For q=1…
We study the early evolution of the electron fraction (or, alternatively, the neutron-to-proton ratio) in the region above the hot proto-neutron star formed after a supernova explosion. We study the way in which the electron fraction in…
We generalize the theory of nuclear decay and capture of Gamow that is based on tunneling through the barrier and internal oscillations inside the nucleus. In our formalism an additional factor is obtained, which describes distribution of…
Allowed weak interaction rates for sd-shell nuclei in stellar environment are calculated using a generalized form of proton-neutron quasiparticle RPA model with separable Gamow-Teller forces. Twelve different weak rates are calculated for…
Measurements of explosive nucleosynthesis yields in core-collapse supernovae provide tests for explosion models. We investigate constraints on explosive conditions derivable from measured amounts of nickel and iron after radioactive decays…
We present shell model calculations of nuclear neutrino energy spectra for 70 $sd$-shell nuclei over the mass number range $A=21-35$. Our calculations include nuclear excited states as appropriate for the hot and dense conditions…
For the first time, the $(d,{}^2\text{He})$ reaction was successfully used in inverse kinematics to extract the Gamow-Teller transition strength in the $\beta^{+}$ direction from an unstable nucleus. The nucleus studied was $^{14}$O, and…
Neutrino reaction cross-sections, $(\nu_\mu,\mu^-)$, $(\nu_e,e^-)$, $\mu$-capture and photoabsorption rates on $^{12}$C are computed within a large-basis shell-model framework, which included excitations up to $4\hbar\omega$. When…
$\beta$-decay and positron decay are believed to play a consequential role during the late phases of stellar evolution of a massive star culminating in a supernova explosion. Recently the microscopic calculation of weak-interaction mediated…
The radiative thermal neutron capture cross sections over the range of thermal energies from 1 keV to 1 MeV are studied in statistical Hauser-Feshbach formalism. The optical model potential is constructed by folding the density dependent…
The results of the study of gamma-transition description in fast neutron capture and photofission are presented. Recent experimental data were used, namely, the spectrum of prompt gamma-rays in the energy range 2{\div}18 MeV from 14-MeV…
We explore properties of core-collapse supernova progenitors with respect to the composite uncertainties in the thermonuclear reaction rates by coupling the reaction rate probability density functions provided by the STARLIB reaction rate…
We present the first calculations to follow the evolution of all stable nuclei and their radioactive progenitors in stellar models computed from the onset of central hydrogen burning through explosion as Type II supernovae. Calculations are…
Proton neutron quasiparticle RPA is used for the first time to calculate weak interaction rates for sd and fp shell nuclei at high temperatures and densities. The calculated rates take into consideration the latest experimental energy…
Lepton (electron and positron) capture rates on iron-regime nuclei are an essential element for modeling the late stages in the evolution of massive stars that end as core-collapse and thermonuclear supernovae. Previous simulation studies…
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…
In dense astrophysical plasmas, neutron capture populates highly excited nuclear states close to the neutron threshold. The impact of additional low-energy nuclear excitations via coupling to the atomic shell on the ability of the so-formed…
Accurate estimate of neutrino energy loss rates are needed for the study of the late stages of the stellar evolution, in particular for cooling of neutron stars and white dwarfs. The energy spectra of neutrinos and antineutrinos arriving at…