Related papers: Pop III Stellar Masses and IMF
We report results from numerical simulations of star formation in the early universe that focus on the dynamical behavior of metal-free gas under different initial and environmental conditions. In particular we investigate the role of…
From studying the cosmic microwave background, we know our Universe started out very simple. It was by and large homogeneous and isotropic, with small fluctuations that can be described by linear perturbation theory. In stark contrast, the…
Disc fragmentation plays an important role in determining the number of primordial stars (Pop III stars), their masses, and hence the initial mass function. In this second paper of a series, we explore the effect of uniform FUV…
Detection of the first stars has remained elusive so-far but their presence may soon be unveiled by upcoming JWST observations. Previous studies have not investigated the entire possible range of halo masses and redshifts which may help in…
We studied the effects of a hypothetical initial stellar generation (PopIII) of only massive and very massive stars (VMS) on the chemical evolution of the Galaxy. We adopted the two-infall chemical evolution model of Chiappini et al. and…
We calculate evolution, collapse, explosion, and nucleosynthesis of Population III very-massive stars with 500$M_{\odot}$ and 1000$M_{\odot}$. Presupernova evolution is calculated in spherical symmetry. Collapse and explosion are calculated…
The first stars continue to elude modern telescopes, but much has been accomplished in observing the glow of the first galaxies. As detection capabilities improve we will eventually resolve these galaxies, but hopes of observing an…
Pristine stars with masses between ~140 and 260 M_sun are theoretically predicted to die as pair-instability supernovae. These very massive progenitors could come from Pop III stars in the early universe. We model the light curves and…
We calculate presupernova evolutions and supernova explosions of massive stars (M=13-25 Mo) for various metallicities. We find the following characteristic abundance patterns of nucleosynthesis in the metal-free (Pop III) stars. (1) The…
Detection of the radiation emitted from some of the earliest galaxies will be made possible in the next decade, with the launch of the James Webb Space Telescope (JWST). A significant fraction of these galaxies may host Population (Pop) III…
Many questions in physical cosmology regarding the thermal history of the intergalactic medium, chemical enrichment, reionization, etc. are thought to be intimately related to the nature and evolution of pregalactic structure. In particular…
Context: Population III (Pop III) stars may be fast rotating. An expected consequence of fast rotation is strong internal mixing that deeply affects their evolutionary tracks in the Hertzsprung-Russell diagram and hence their ionising…
We observe a sharp transition from a singular, high-mass mode of star formation, to a low-mass dominated mode, in numerical simulations, at a metallicity of 10^-3 Zsolar. We incorporate a new method for including the radiative cooling from…
Using self-consistent chemodynamical simulations including star formation, supernova feedback, and chemical enrichment, I show the dependence of cosmic star formation and chemical enrichment histories on the initial mass function (IMF). The…
We review the current status of knowledge concerning the early phases of star formation during cosmic dawn. This includes the first generations of stars forming in the lowest mass dark matter halos in which cooling and condensation of gas…
The James Webb Space Telescope (JWST) has revealed a population of active galactic nuclei (AGNs) that challenge existing black hole (BH) formation models. These newly observed BHs seem overmassive compared to the host galaxies and have an…
Recent numerical simulations of the fragmentation of primordial molecular clouds in hierarchical cosmogonies have suggested that the very first stars (the so-called Population III) may have been rather massive. Here we point out that a…
We present a new analysis of the abundances observed in extremely metal poor stars based on both a new generation of theoretical presupernova models and explosions of zero metallicity massive stars and a new abundance analysis of an…
The rate of long-duration gamma-ray bursts (GRBs) from isolated Pop III stars is not well known, as it depends on our poor understanding of their initial mass function (IMF), rotation rates, stellar evolution, and mass loss. Some massive…
We utilize GIZMO, coupled with newly developed sub-grid models for Population~III (Pop~III) and Population~II (Pop~II), to study the legacy of star formation in the pre-reionization Universe. We find that the Pop~II star formation rate…