Related papers: Presupernova Evolution with Improved Rates for Wea…
We provide progenitor models for electron capture supernovae (ECSNe) with detailed evolutionary calculation. We include minor electron capture nuclei using a large nuclear reaction network with updated reaction rates. For electron captures,…
Supernovae (SNe) powered by interaction with circumstellar material provide evidence for intense stellar mass loss during the final years leading up to core collapse. We have argued that during and after core neon burning, internal gravity…
Proton-neutron quasi-particle random phase approximation (pn-QRPA) theory has recently being used for calculation of stellar weak interaction rates of $fp$-shell nuclide with success. Neutrino losses from proto-neutron stars play a pivotal…
We present Gamow-Teller strength distributions from shell model Monte Carlo studies of fp-shell nuclei that may play an important role in the pre-collapse evolution of supernovae. We then use these strength distributions to calculate the…
Core-collapse supernovae may depend sensitively on charged current neutrino interactions in warm, low density neutron rich matter. A proton in neutron rich matter is more tightly bound than is a neutron. This energy shift \Delta U increases…
At densities between 10^8 and 10^10} g/cm^3 electron capture in a presupernova collapse is believed to mainly occur on odd-odd nuclei. We have derived the rates for six of the most important electron capturing nuclei, {54,56,58}Mn and…
Weak-interaction rates, including beta-decay and electron capture, are studied in several odd-A nuclei in the pf-shell region at various densities and temperatures of astrophysical interest. Special attention is paid to the relative…
The Gamow-Teller strength distribution from ${}^{88}$Sr was extracted from a $(t,{}^{3}\text{He}+\gamma)$ experiment at 115 MeV/$u$ to constrain estimates for the electron-capture rates on nuclei around $N=50$, between and including…
In the late progressive stages of heavy stars, electron capture and $\beta^\pm$-decay are the governing processes. The weak rates are essential inputs for modeling the stages of high-mass stars before supernova explosions. As per results…
A significant fraction of stars between 7-11 solar masses are thought to become supernovae, but the explosion mechanism is unclear. The answer depends critically on the rate of electron capture on $^{20}$Ne in the degenerate oxygen-neon…
The success or failure of the neutrino-transport mechanism for producing a supernova in an evolved massive star is known to be sensitive not only to the mass of the iron core that collapses, but also to the density gradient in the silicon…
The diffuse $\gamma$-ray emission from short-lived radioactive $^{26}$Al and $^{60}$Fe provides a direct probe of ongoing nucleosynthesis in the Galaxy. However, theoretical models have long struggled to reproduce the observed…
With presently known input physics and computer simulations in 1D, a self-consistent treatment of core collapse supernovae does not yet lead to successful explosions, while 2D models show some promise. Thus, there are strong indications…
The thermonuclear explosion of massive white dwarfs is believed to explain at least a fraction of Type Ia supernovae (SNIa). After thermal runaway, electron captures on the ashes left behind by the burning front determine a loss of…
We model the late evolution and mass loss history of rapidly rotating Wolf-Rayet stars in the mass range $5\,\rm{M}_{\odot}\dots 100\,\rm{M}_{\odot}$. We find that quasi-chemically homogeneously evolving single stars computed with enhanced…
This work presents the microscopic calculation of energy rates ({\gamma} ray heating and (anti)neutrino cooling rates) due to weak decay of selected Fe isotopes. The isotopes have astrophysical significance during the presupernova evolution…
We present shell model calculations of electron capture strength distributions in A=28 nuclei and computations of the corresponding capture rates in supernova core conditions. We find that in these nuclei the Brink-Axel hypothesis for the…
The evolutionary pathways of core-collapse supernova progenitors at the low-mass end of the spectrum are beset with major uncertainties. In recent years, a variety of evolutionary channels has been discovered in addition to the classical…
Few white dwarfs, located in binary systems, may acquire sufficiently high mass accretion rates resulting in the burning of carbon and oxygen under nondegenerate conditions forming a O+Ne+Mg core. These O+Ne+Mg cores are gravitationally…
We calculate the weak interaction rates of selected light nuclei during the epoch of Big Bang Nucleosynthesis (BBN), and we assess the impact of these rates on nuclear abundance flow histories and on final light element abundance yields. We…