Related papers: Supernova Fallback: A Possible Site for the r-Proc…
Massive stars end their life in an explosion event with kinetic energies of the order 1 Bethe. Immediately after the explosion has been launched, a region of low density and high entropy forms behind the ejecta which is continuously subject…
We consider the explosion of supernovae and the possible production of a variety of high energy transients by delayed black hole formation in massive stars endowed with rotation. Following the launch of a ``successful'' shock by the usual…
Neutron star mergers are today considered a major production site for rapid neutron capture elements. While the bulk of the matter escapes at fast, but non-relativistic velocities (${\sim} 0.2\,c$), a small amount of the dynamically ejected…
The production of elements by rapid neutron capture (r-process) in neutron-star mergers is expected theoretically and is supported by multimessenger observations of gravitational-wave event GW170817: this production route is in principle…
The heaviest chemical elements are naturally produced by the rapid neutron-capture process (r-process) during neutron star mergers or supernovae. The r-process production of elements heavier than uranium (transuranic nuclei) is poorly…
We examine the characteristics of nucleosynthesis in 'hypernovae', i.e., supernovae with very large explosion energies ($ \gsim 10^{52} $ ergs). We carry out detailed nucleosynthesis calculations for these energetic explosions and compare…
We numerically investigate the dynamics of a supernova fallback accretion confronting with a relativistic wind from a newborn neutron star (NS). The time evolution of the accretion shock in the radial direction is basically characterized by…
The existence of neutron star mergers has been supported since the discovery of the binary pulsar and the observation of its orbital energy loss, consistent with General Relativity. They are considered nucleosynthesis sites of the rapid…
We present a new nucleosynthesis process, that we denote nu p-process, which occurs in supernovae (and possibly gamma-ray bursts) when strong neutrino fluxes create proton-rich ejecta. In this process, antineutrino absorptions in the…
We examine the Pb and Th abundances in 27 metal-poor stars (-3.1 < [Fe/H] < -1.4) whose very heavy metal (Z > 56) enrichment was produced only by the rapid (r-) nucleosynthesis process. New abundances are derived from HST/STIS, Keck/HIRES,…
We investigate the nucleosynthesis of heavy elements in the winds ejected by accretion disks formed in neutron star mergers. We compute the element formation in disk outflows from hypermassive neutron star (HMNS) remnants of variable…
We study the neutrino-driven wind from the proto-neutron star by the general relativistic hydrodynamical simulations. We examine the properties of the neutrino-driven wind to explore the possibility of the r-process nucleosynthesis. The…
The huge neutrino pulse that occurs during the collapse of a massive stellar core, is expected to contribute to the origination of a number of isotopes both of light chemical elements and heavy ones. It is shown that, in general, the…
We demonstrate that rapid expansion of the shocked surface layers of an O-Ne-Mg core following its collapse can result in r-process nucleosynthesis. As the supernova shock accelerates through these layers, it makes them expand so rapidly…
We test the hypothesis that the observed first-peak (Sr, Y, Zr) and second-peak (Ba) s-process elemental abundances in low-metallicity Milky Way stars, and the abundances of the elements Mo and Ru, can be explained by a pervasive r-process…
Merging neutron stars produce "kilonovae"---electromagnetic transients powered by the decay of unstable nuclei synthesized via rapid neutron capture (the r-process) in material that is gravitationally unbound during inspiral and…
We investigate nucleosynthesis in the sub-relativistic outflows from black hole (BH) accretion disks formed in failed supernovae from rapidly-rotating Wolf-Rayet stars. These disks reach the neutrino-cooled regime during a portion of their…
Expulsion of neutron-rich matter following the merger of neutron star (NS) binaries is crucial to the radioactively-powered electromagnetic counterparts of these events and to their relevance as sources of r-process nucleosynthesis. Here we…
Rapid neutron capture process (r-process) elements have been detected in a large fraction of metal-poor halo stars, with abundances relative to iron (Fe) that vary by over two orders of magnitude. This scatter is reduced to less than a…
Along with binary neutron star mergers, the in-spiral and merger of a black hole and a neutron star is a predicted site of $r$-process nucleosynthesis and associated kilonovae. For the right mass ratio, very large amounts of neutron rich…