Related papers: Shell and explosive hydrogen burning
Nuclear astrophysics aims at unraveling the cosmic origins of chemical elements and the physical processes powering stars. It constitutes a truly multidisciplinary field, that integrates tools, advancements, and accomplishments from…
Some catastrophic stellar explosions, such as supernovae (SNe), compact binary coalescences, and micro-tidal disruption events, are believed to be embedded in the accretion disks of active galactic nuclei (AGN). We show high-energy…
The explosion of a white dwarf of mass 1.36 M$_\odot$ has been simulated in three dimensions with the aid of a SPH code. The explosion follows the delayed detonation paradigma. In this case the deflagration-detonation transition is induced…
We perform 2-dimensional relativistic hydrodynamical simulations in the context of collapsar model. Calculations of explosive nucleosynthesis are also accomplished. We investigate the influence of the structure of the progenitor and energy…
Neutron stars (NSs) and black holes (BHs) are born when the final collapse of the stellar core terminates the lives of stars more massive than about 9 Msun. This can trigger the powerful ejection of a large fraction of the star's material…
We study the sensitivity of presupernova evolution and supernova nucleosynthesis yields of massive stars to variations of the helium-burning reaction rates within the range of their uncertainties. We use the current solar abundances from…
We explore the dependence of pre-supernova evolution and supernova nucleosynthesis yields on the uncertainties in helium burning reaction rates. Using the revised solar abundances of Lodders (2003) for the initial stellar composition,…
We review the characteristics of nucleosynthesis in 'Hypernovae', i.e., core-collapse supernovae with very large explosion energies ($ \gsim 10^{52} $ ergs). The hypernova yields show the following characteristics: 1) The mass ratio between…
Classical nova explosions and type I X-ray bursts are the most frequent types of thermonuclear stellar explosions in the Galaxy. Both phenomena arise from thermonuclear ignition in the envelopes of accreting compact objects in close binary…
High-redshift active galactic nuclei (AGN) serve as powerful probes of early black-hole growth, galaxy formation, and the evolving intergalactic medium (IGM). In this work, we use Lumina, a cosmological radiation-hydrodynamic simulation…
We review the characteristics of nucleosynthesis in 'Hypernovae', i.e., supernovae with very large explosion energies ($ \gsim 10^{52} $ ergs). The hypernova yields compared to those of ordinary core-collapse supernovae show the following…
We review the state of the art in modelling lithium production, through the Cameron-Fowler mechanism, in two stellar sites: during nova explosions and in the envelopes of massive asymptotic giant branch (AGB) stars. We also show preliminary…
I study the possibility that within the frame of the core degenerate (CD) scenario for type Ia supernovae (SNe Ia) the merger process of the core of the asymptotic giant branch (AGB) star and the white dwarf (WD) maintains an envelope mass…
Nuclear reactions are responsible for the chemical evolution of stars, galaxies and the Universe. Unfortunately, at temperatures of interest for nuclear astrophysics, the cross-sections of the thermonuclear reactions are in the…
We examine electron-capture supernovae (ECSNe) as sources of elements heavier than iron in the solar system and in Galactic halo stars. Nucleosynthesis calculations are performed on the basis of thermodynamic histories of mass elements from…
I discuss the relationship between mass loss and nucleosynthesis on the Asymptotic Giant Branch (AGB). Because of thermal pulses and possibly other mixing processes, products of nucleosynthesis can be brought to the surface of AGB stars,…
The hydrogen-deficiency in extremely hot post-AGB stars of spectral class PG1159 is probably caused by a (very) late helium-shell flash or a AGB final thermal pulse that consumes the hydrogen envelope, exposing the usually-hidden intershell…
The nucleosynthetic yield from a supernova explosion depends upon a variety of effects: progenitor evolution, explosion process, details of the nuclear network, and nuclear rates. Especially in studies of integrated stellar yields,…
Accreting neutron stars exhibit Type I X-ray bursts from both frequent hydrogen/helium flashes as well as rare carbon flashes. The latter (superbursts) ignite in the ashes of the former. Hydrogen/helium bursts, however, are thought to…
The oldest stars hide information about the chemical evolution of the early universe. In this contect new models of the AGB stellar evolution phase at very low and zero metallicity are presented. Due to the deficiency or absence of CNO…