Related papers: The first stars
Population III stars are the first stars in the Universe to form at z=20-30 out of a pure hydrogen and helium gas in minihalos of 10^5-10^6 M$_\odot$ . Cooling and fragmentation is thus regulated via molecular hydrogen. At densities above…
We investigate the formation of extremely metal-poor (EMP) stars that are observed in the Galactic halo and neighboring ultra-faint dwarf galaxies. Their low metal abundances (${\rm [Fe/H]} < -3$) indicate that their parent clouds were…
We study the formation of Pop III stars by performing radiation hydrodynamics simulations for three different initial clouds extracted from cosmological hydrodynamics simulations. Starting from the cloud collapse stage, we follow the growth…
There has been considerable theoretical debate over whether photoionization and supernova feedback from the first Population III stars facilitate or suppress the formation of the next generation of stars. We present results from an Eulerian…
We study cosmological simulations of early structure formation, including non-equilibrium molecular chemistry, metal pollution from stellar evolution, transition from population III (popIII) to population II (popII) star formation,…
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 analyze the time evolution of the luminosity of a cluster of Population III protostars formed in the early universe. We argue from the Jeans criterion that primordial gas can collapse to form a cluster of first stars that evolve…
New observations from the Hubble ultra deep field suggest that the star formation rate at z>7 drops off faster than previously thought. Using a newly determined star formation rate for the normal mode of Population II/I stars (PopII/I),…
The first stars are the key to the formation of primitive galaxies, early cosmological reionization and chemical enrichment, and the origin of supermassive black holes. Unfortunately, in spite of their extreme luminosities, individual…
The formation process of Population III (PopIII) stars in the mass accretion phase is investigated by numerical experiments. The barotropic relation of primordial gas and artificial stiffening of the equation of state in very dense regions…
Population III stars were the first stars to form after the Big Bang, and are believed to have made the earliest contribution to the metal content of the universe beyond the products of the Big Bang Nucleosynthesis. These stars are…
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…
We use a spherical hydrodynamics code to show that in cold dark matter cosmologies, the first stars form at z=50 through the direct collapse of gas in low-mass systems (approx 10^4 solar masses). Photons from the first stars easily…
Observing the first generation of Population III (Pop III) stars is one of the most demanding challenges in astronomy. Indeed, Pop III stars are expected to predominantly form within faint minihalos at early times with a top-heavy initial…
The formation of the first galaxies at redshifts z ~ 10-15 signaled the transition from the simple initial state of the universe to one of ever increasing complexity. We here review recent progress in understanding their assembly process…
Stars in star clusters are thought to form in a single burst from a common progenitor cloud of molecular gas. However, massive, old globular clusters -- with ages greater than 10 billion years and masses of several hundred thousand solar…
We numerically study the mutual interaction between dark matter (DM) and Population III (Pop III) stellar systems in order to explore the possibility of Pop III dark stars within this physical scenario. We perform a cosmological simulation,…
The emergence of the first sources of light at redshifts of z ~ 10-30 signaled the transition from the simple initial state of the Universe to one of increasing complexity. We review recent progress in our understanding of the formation of…
The difference in density profiles of the contributions from different density peaks to dark matter halos results in certain expectations about the Milky Way's stellar halo. We cut our simulated halo stars into two populations: those…
We model gas cooling in high-resolution N-body simulations in order to investigate the formation of the first generation of stars. We follow a region of a LCDM universe especially selected to contain a rich cluster by the present day. The…