Related papers: Upper Bound on the First Star Formation History
Population III (or Pop. III) stars, the first stellar generation built up from metal-free primordial gas, first started to form at redshifts z ~ 30. They formed primarily in small dark matter halos with masses of a few million solar masses.…
We present results on the formation of Pop III stars at redshift 7.6 from the Renaissance Simulations, a suite of extremely high-resolution and physics-rich radiation transport hydrodynamics cosmological adaptive-mesh refinement simulations…
The Fermi satellite has detected GeV emission from a number of gamma-ray bursts and active galactic nuclei at high redshift, z > 1.5. We examine the constraints that the detections of gamma rays from several of these sources place on the…
The nature of the first, so-called Population III (Pop III) stars has for long remained largely unconstrained. However, the James Webb Space Telescope (JWST) finally opened new concrete prospects for their detection during the Epoch of…
By employing a simple semi-analytical star formation model where the formation rates of Population (Pop) I/II and III stars can be calculated, respectively, we account for the number distribution of gamma-ray bursts (GRBs) with high…
[abridged] The First Stars in the Universe form out of pristine primordial gas clouds that have been radiatively cooled to a few hundreds of degrees Kelvin either via molecular or atomic (Lyman-Alpha) hydrogen lines. This primordial mode of…
We perform high-resolution cosmological hydrodynamic simulations to study the formation of the first galaxies that reach the masses of $10^{8-9}~h^{-1}~M_\odot$ at $z=9$. The resolution of the simulations is high enough to resolve…
We present a revised measurement of the optical extragalactic background light (EBL), based on the contribution of resolved galaxies to the integrated galaxy light (IGL). The cosmic optical background radiation (COB), encodes the light…
The character of the first galaxies at redshifts z > 10 strongly depends on their level of pre-enrichment, which is in turn determined by the rate of primordial star formation prior to their assembly. In order for the first galaxies to…
We investigate the impact of an early population of massive stars on their surroundings. Dissociation of molecular hydrogen by strong UV emission from such stars is expected to produce a global transition in the cooling mechanism of…
In this paper, we obtain the NIRB and SBGWs from the early stars, which are constrained by the observation of reionization and star formation rate. We study the transition from Pop III to Pop II stars via the star formation model of…
Identifying stars formed in pristine environments (Pop III) within the first billion years is vital to uncovering the earliest growth and chemical evolution of galaxies. Pop III galaxies, however, are typically expected to be too faint and…
Pop III stars are typically massive stars of primordial composition forming at the centers of the first collapsed dark matter structures. Here we estimate the optimal X-ray emission in the early universe for promoting the formation of Pop…
The epoch of reionization and formation of first stars are inter-linked topics that are of considerable interest. We use a simplified approach for studying formation of stars in collapsed haloes, and the resulting ionization of the…
The quest to find the first stars has driven astronomers across cosmic time, from hopes to identify their signatures in their heyday at cosmic dawn to deep searches for their remnants in our local neighborhood. Such work crucially relies on…
We investigate the formation of metal-free, Population III (Pop III), stars within a minihalo at z ~ 20 with a smoothed particle hydrodynamics (SPH) simulation, starting from cosmological initial conditions. Employing a hierarchical,…
We present a semi-analytic model of star formation in the early universe, beginning with the first metal-free stars. By employing a completely feedback-limited star formation prescription, stars form at maximum efficiency until the…
We combine fast radiative transfer calculations with high resolution hydrodynamical simulations to study an epoch of early hydrogen reionisation by primordial stellar sources at redshifts 15<z<30. With relatively conservative assumptions,…
Cosmological hydrodynamic simulations have significantly improved over the past several years, and we have already shown that the observed properties of Lyman-break galaxies (LBGs) at z=3 can be explained well by the massive galaxies in the…
We simulate a plausible cosmological model in considerable physical and numerical detail through the successive phases of reheating (at 10<z<20), formation of Pop III stars at z=15 (due to molecular hydrogen cooling), with subsequent…