Related papers: Explosion and nucleosynthesis of low redshift pair…
Aims: To gain better insight on the physics of stripped-envelope core-collapse supernovae through studying their environments. Methods: We obtained low-resolution optical spectroscopy with the New Technology Telescope (+ EFOSC2) at the…
We present a set of nonlocal thermodynamic equilibrium steady-state calculations of radiative transfer for one-year old type II supernovae (SNe) starting from state-of-the-art explosion models computed with detailed nucleosynthesis. This…
We analyse two recent computations of type II supernova nucleosynthesis by Woosley & Weaver (1995, WW95) and Thielemann, Nomoto, & Hashimoto (1996, TNH96), focusing on the ability to reproduce the observed [Mg/Fe]-ratios in various galaxy…
Low metallicity very massive stars with an initial mass between 140 Mo and 260 Mo can be subdivided into two groups: those between 140 Mo and 200 Mo which produce a relatively small amount of Fe, and those with a mass between 200 Mo and 260…
We recently determined the mass of the most massive star known to the date, R136a1 with a mass at birth 320 times the mass of our sun, as well as the mass of several other stars that are more massive than 150 M. Such massive stars (~150-300…
We propose a temperature-resolved Monte Carlo (MC) approach to identify the temperature regimes in which low-energy helium-burning reaction rates most strongly affect nucleosynthesis in very massive stars that undergo pair-instability…
Superluminous supernovae have been proposed to arise from Population III progenitors that explode as pair-instability supernovae. Pop III stars are the first generation of stars in the Universe, and are thought to form as late as $z \sim…
Observational evidence suggests that some very massive stars in the local Universe may die as pair-instability supernovae. We present 2D simulations of the pair-instability supernova of a non-zero metallicity star. We find that very little…
The explosion of ultra-stripped stars in close binaries may explain new discoveries of weak and fast optical transients. We have demonstrated that helium star companions to neutron stars (NSs) may evolve into naked metal cores as low as…
We investigate the chemical evolution of odd-numbered elements such as sodium (Na) and aluminum (Al) during the early epochs of the Galactic halo with the use of a model that reproduces the observed box-shaped distribution of extremely…
Massive stars having a CO core of $\sim$40-60 M$_\odot$ experience pulsational pair-instability (PPI) after carbon-burning. This instability induces strong pulsations of the whole star and a part of outer envelope is ejected. We investigate…
Recent JWST observations have revealed a population of unexpectedly bright sources at ultra-high redshift ($z > 15$), challenging current models of early galaxy formation. One extreme example is 'Capotauro', an F356W-dropout identified in…
The assembly of supermassive black holes poses a challenge primarily because of observed quasars at high redshift, but additionally because of the current lack of observations of intermediate mass black holes. One plausible scenario for…
The effects of rotation on stellar evolution are particularly important at low metallicity, when mass loss by stellar winds diminishes and the surface enrichment due to rotational mixing becomes relatively more pronounced than at high…
We propose a semi-analytic model that is developed to understand the cosmological evolution of the mean metallicity in the Universe. In particular, we study the contributions of Population III (Pop III) and Population II (Pop II) stars to…
Type Ia supernova explosions (SNIa) are fundamental sources of elements for the chemical evolution of galaxies. They efficiently produce intermediate-mass (with Z between 11 and 20) and iron group elements - for example, about 70% of the…
We present numerical simulations to describe the nucleosynthesis and evolution of pre-Galactic clouds in a model which is motivated by cold dark matter simulations of hierarchical galaxy formation. We adopt a SN-induced star-formation…
Core-collapse supernovae, occurring at the end of massive star evolution, produce heavy elements, including those in the iron peak. Although the explosion mechanism is not yet fully understood, theoretical models can reproduce optical…
In Limongi et al. (2024) we presented and discussed the main evolutionary properties and final fate of stars in the mass range 7-15 Msun. The evolutions of those models were computed by means of a medium size nuclear network that guaranteed…
The interstellar medium of low-metallicity systems undergoing star formation will show chemical abundance inhomogeneities due to supernova events enriching the medium on a local scale. If the star formation time-scale is shorter than the…