Related papers: Where, oh where has the r-process gone?
Abundances of heavier elements (barium and beyond) in many neutron-capture-element-rich halo stars accurately replicate the solar system r-process pattern. However, abundances of lighter neutron-capture elements in these stars are not…
An update on astrophysical models for nucleosynthesis via rapid neutron capture, the r process, is given. A neutrino-induced r process in supernova helium shells may have operated up to metallicities of ~10^-3 times the solar value. Another…
We solve the general-relativistic steady-state eigenvalue problem of neutrino-driven protoneutron star winds, which immediately follow core-collapse supernova explosions. We provide velocity, density, temperature, and composition profiles…
We explore heavy element nucleosynthesis in neutrino-driven winds from rapidly-rotating, strongly magnetized proto-neutron stars for which the magnetic dipole is aligned with the rotation axis, and the field is assumed to be a static…
Heavy elements like gold, platinum or uranium are produced in the r-process, which needs neutron-rich and explosive environments. Neutron star mergers are a promising candidate for an r-process site. They exhibit three different channels…
There are many candidate sites of the r-process: core-collapse supernovae (including rare magnetorotational core-collapse supernovae), neutron star mergers, and neutron star/black hole mergers. The chemical enrichment of…
The rapid neutron-capture process or r-process is thought to produce the majority of the heavy elements (Z > 30) in extremely metal-poor stars. The same process is also responsible for a significant fraction of the heavy elements in the…
Recent hydrodynamic simulations of core-collapse supernovae with accurate neutrino transport suggest that the bulk of the early neutrino-heated ejecta is proton rich, in which the production of some interesting proton-rich nuclei is…
We present a model to explain the wide range of abundances for heavy r-process elements (mass number A > 130) at low [Fe/H]. This model requires rapid star formation and/or an initial population of supermassive stars in the earliest…
The rapid neutron-capture process (r-process) is responsible for the creation of roughly half of the elements heavier than iron, including precious metals like silver, gold, and platinum, as well as radioactive elements such as thorium and…
We examine r-process nucleosynthesis in a "prompt supernova explosion" from an 8-10 Msun progenitor star, as an alternative scenario to the "neutrino wind" mechanism. In the present model, the progenitor star has formed an…
Various nucleosynthesis studies have pointed out that the r-process elements in very metal-poor (VMP) halo stars might have different origins. By means of familiar concepts from statistics (correlations, cluster analysis, rank tests of…
We present the distributions of elemental abundance ratios using chemodynamical simulations which include four different neutron capture processes: magneto-rotational supernovae, neutron star mergers, neutrino driven winds, and electron…
It is argued that the abundances of r-process related elements in stars with -3<[Fe/H]<-1 can be explained by the contributions of three sources. The sources are: the first generations of very massive (>100 solar masses) stars that are…
We investigated r-process nucleosynthesis in magneto-rotational supernovae, based on a new explosion mechanism induced by the magneto-rotational instability. A series of axisymmetric magneto-hydrodynamical simulations with detailed…
Theoretical studies of the nucleosynthesis origin of the heavy elements in our Solar System (S.S.) by the rapid neutron-capture process (r-process) still face the entwined uncertainties in the possible astrophysical scenarios and the…
The dispersion and mean trends of r-process abundances in metal-poor stars are discussed based on a model of diverse supernova sources for the r-process. This model is unique in that its key parameters are inferred from solar system data…
An r-process scenario with fission but no fission cycling is considered to account for the observed abundance patterns of neutron-capture elements in ultra-metal-poor stars. It is proposed that neutrino reactions play a crucial role in…
The origin of heavy r-process elements in the universe is still a matter of great debate, with a confirmed scenario being neutron star (NS) mergers. Additional relevant sites could be specific classes of events, such as gamma-ray burst…
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…