Related papers: Spallative Nucleosynthesis in Supernova Remnants. …
From a recent re-analysis of the available data, Be and B Galactic evolution appears to show evidence for a two-slope behaviour with respect to O. The inferred Be/O abundance ratio in halo stars is constant at very low metallicity (primary…
Light element nucleosynthesis is an important chapter of nuclear astrophysics. Specifically, the rare and fragile light nuclei Lithium, Beryllium and Boron (LiBeB) are not generated in the normal course of stellar nucleosynthesis (except…
There is continued interest in the possibility that big bang nucleosynthesis may produce significant quantities of Be and B. In this paper we reevaluate the primordial abundances taking into account uncertainties in reactions rates. We…
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…
To understand better the early galactic production of Li, Be, and B by cosmic ray spallation and fusion reactions, the dependence of these production rates on cosmic ray models and model parameters is examined. The sensitivity of elemental…
The light elements, Li, Be, and B, provide tracers for many aspects of astronomy including stellar structure, Galactic evolution, and cosmology. We have taken spectra of Be in 117 metal-poor stars ranging in metallicity from [Fe/H] = -0.5…
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 calculate the production rates of Li6, Li7, Be9, B10 and B11 via spallation of Carbon, Nitrogen and Oxygen nuclei by protons and alpha-particles and by alpha-alpha fusion reactions. We include recent measurements of the cross sections of…
Explosions of type Ic supernovae (SNe Ic) are investigated using a relativistic hydrodynamic code to study roles of their outermost layers of the ejecta in light element nucleosynthesis through spallation reactions as a possible mechanism…
The first metal enrichment in the universe was made by supernova (SN) explosions of population (Pop) III stars. The trace remains in abundance patterns of extremely metal-poor (EMP) stars. We investigate the properties of nucleosynthesis in…
We review the nucleosynthesis yields of core-collapse supernovae (SNe) for various stellar masses, explosion energies, and metallicities. Comparison with the abundance patterns of metal-poor stars provides excellent opportunities to test…
As an explosion develops in the collapsed core of a massive star, neutrino emission drives convection in a hot bubble of radiation, nucleons, and pairs just outside a proto-neutron star. Shortly thereafter, neutrinos drive a wind-like…
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…
Supernova remnants (SNRs) are the outcome of supernovae (SNe, either core-collapse or thermonuclear). The remnant results from the interaction between the stellar ejecta and the ambient medium around the progenitor star. Young SNRs are…
This paper is superseded by Arxiv:1911.07334. Big-bang nucleosynthesis (BBN) is a valuable tool to constrain the physics of the early universe and is the only probe of the radiation-dominated epoch. A fundamental assumption in BBN is that…
Big Bang nucleosynthesis in the presence of decaying relic neutral particles is examined in detail. All non-thermal processes important for the determination of light-element abundance yields of 2H, 3H, 3He, 4He, 6Li, and 7Li are coupled to…
We perform a comparative analysis of nucleosynthesis yields from binary neutron star (BNS) mergers, black hole-neutron star (BHNS) mergers, and core-collapse supernovae (CCSNe) with the goal of determining which are the most dominant…
Core-collapse supernovae (CCSNe) are the extremely energetic deaths of massive stars. They play a vital role in the synthesis and dissemination of many heavy elements in the universe. In the past, CCSN nucleosynthesis calculations have…
We determine the contributions of the rapid (r) and slow (s) neutron capture processes to the Ba isotope mixture, along with Ba, Eu, and Sr NLTE abundances, in a sample of very metal-poor stars. The selected stars formed before the…
As part of a large survey of halo and thick disc stars, we found one halo star, HD 106038, exceptionally overabundant in beryllium. In spite of its low metallicity, [Fe/H] = -1.26, the star has log(Be/H) = -10.60, which is similar to the…