Related papers: Constraining the PopIII IMF with high-z GRBs
We study the contribution of binary black hole (BH-BH) mergers from the first, metal-free stars in the Universe (Pop III) to gravitational wave detection rates. Our study combines initial conditions for the formation of Pop III stars based…
We present results from the first cosmological simulations which study the onset of primordial, metal-free (population III), cosmic star formation and the transition to the present-day, metal-rich star formation (population II-I), including…
We use N-body simulations to study the dynamical evolution of Population III (Pop III) stellar systems and the resulting binary statistics. We design a physically-motivated framework for the initial conditions of Pop III star clusters,…
We present the evolution of rotation in models of massive single stars covering a wide range of masses and metallicities. These models reproduce very well observations during the early stages of the evolution (in particular WR populations…
We show that a relativistic gamma-ray burst (GRB) jet can potentially pierce the envelope of very massive first generation star (Population III; Pop III) by using the stellar density profile to estimate both the jet luminosity (via…
Star formation in the early Universe has left its imprint on the chemistry of observable stars in galaxies. We derive elemental abundances and the slope of the low-mass end of the initial mass function (IMF) for a sample of 25 very massive…
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…
The transition from Population III to Population II stars is determined by the presence of a sufficient amount of metals, in particular, oxygen and carbon. The vastly different yields of these relevant metals between different initial…
A robust stellar initial mass function (IMF) is crucial in any studies related to star formation. However, the direct measurement of the stellar IMF is confined to the local universe, limited by the resolving power of telescopes. Recently,…
Few topics in astronomy initiate such vigorous discussion as whether or not the initial mass function (IMF) of stars is universal, or instead sensitive to the initial conditions of star formation. The distinction is of critical importance:…
Much of our knowledge of galaxies comes from analysing the radiation emitted by their stars. It depends on the stellar initial mass function (IMF) describing the distribution of stellar masses when the population formed. Consequently…
We review the expected properties of Pop III and very metal-poor starburst and the behaviour the Lyman-alpha and HeII 1640 emission lines, which are most likely the best/easiest signatures to single out such objects. Existing claims of Pop…
A number of recent studies have proposed that the stellar initial mass function (IMF) of early type galaxies varies systematically as a function of galaxy mass, with higher mass galaxies having bottom heavy IMFs. These bottom heavy IMFs…
Does the IMF vary? Is it significantly different in metal-rich environments than in metal-poor ones? Theoretical work predicts this to be the case. But in order to provide robust empirical evidence for this, the researcher must understand…
We review the uncertainties in high-z star-formation rate (SFR) measures and the constraints that one obtains from high-z gamma-ray burst (GRB) rates on them. We show that at the present time, the GRB rates per unit star-formation at z>3…
Long-duration gamma-ray bursts (GRBs) are associated with the death of metal-poor massive stars. Even though they are highly transient events very hard to localize, they are so bright that they can be detected in the most difficult…
We discuss the link between dark matter halos hosting the first PopIII stars formed at redshift z > 40 and the rare, massive, halos that are generally considered to host bright z~6 quasars. We show that within the typical volume occupied by…
An X-ray background in the early Universe enhances molecular hydrogen formation, the main coolant of primordial gas, thereby lowering the threshold for Pop III star formation. Continuing our series on X-ray impacts on Pop III star…
We discuss the cosmological significance of the transition from the Pop III to Pop II mode of star formation in the early universe, and when and how it may occur in primordial galaxies. Observations that could detect this transition include…
I discuss current theoretical expectations of how primordial, Pop III.1 stars form. Lack of direct observational constraints makes this a challenging task. In particular predicting the mass of these stars requires solving a series of…