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The formation of the first low-mass stars from gas with low carbon and oxygen abundances
It is shown that as soon as the primordial gas—left over from the Big Bang—is enriched by elements ejected from supernovae to a carbon or oxygen abundance as small as ∼0.01–0.1 per cent of that found in the Sun, cooling by singly ionized carbon or neutral oxygen can lead to the formation of low-mass stars by allowing cloud fragmentation to smaller clumps. Expand
Formation of the First Supermassive Black Holes
We consider the physical conditions under which supermassive black holes could have formed inside the first galaxies. Our smoothed particle hydrodynamics simulations indicate that metal-free galaxiesExpand
The fragmentation of pre-enriched primordial objects
Recent theoretical investigations have suggested that the formation of the very first stars, forming out of metal-free gas, was fundamentally different from the present-day case. The question thenExpand
The Formation of the First Stars. I. The Primordial Star-forming Cloud
To constrain the nature of the very first stars, we investigate the collapse and fragmentation of primordial, metal-free gas clouds. We explore the physics of primordial star formation by means ofExpand
The formation of a star cluster: predicting the properties of stars and brown dwarfs
We present results from the largest numerical simulation of star formation to resolve the fragmentation process down to the opacity limit. The simulation follows the collapse and fragmentation of aExpand
Generic Spectrum and Ionization Efficiency of a Heavy Initial Mass Function for the First Stars
We calculate the generic spectral signature of an early population of massive stars at high redshifts. For metal-free stars with mass above 300 M☉, we find that the combined spectral luminosity perExpand
The cosmic dark ages ended a few hundred million years after the big bang, when the first stars began to fill the universe with new light. It has generally been argued that these stars formed inExpand
High-redshift gamma-ray bursts from population III progenitors
Detection of gamma-ray bursts (GRBs) from redshifts z k7 would open a new window into the earliest epoch ofExpand
Formation and evolution of primordial protostellar systems
We investigate the formation of the first stars at the end of the cosmic dark ages with a suite of three-dimensional, moving-mesh simulations that directly resolve the collapse of the gas beyond theExpand
The First Stars
Abstract The formation of the first generations of stars at redshifts z ≥ 15 − 20 signaled the transition from the simple initial state of the universe to one of ever increasing complexity. We hereExpand