Related papers: A model for microquasars of Population III
The recent detection of the sky-averaged 21-cm cosmological signal indicates a stronger absorption than the maximum allowed value based on the standard model. One explanation for the required colder primordial gas is the energy transfer…
After the so-called cosmic recombination, the expanding universe entered into a period of darkness since most of the matter was in a neutral state. About a billion years later, however, the intergalactic space was once again ionized. The…
We use large-scale cosmological simulations to study the prospect of observing Population III (Pop III) bright galaxies with the James Webb Space Telescope (JWST). To quantify the impact of radiative transfer (RT), we compare a simulation…
We revisit the formation and evolution of the first galaxies using new hydrodynamic cosmological simulations with the ART code. Our simulations feature a recently developed model for H2 formation and dissociation, and a star formation…
The first star clusters and quasars resulted directly from the growth of linear density fluctuations in the early Universe. Since they emerged from a well-defined set of initial conditions, the interplay between observational data from the…
The formation of massive stars in close binary systems is complicated due to their high radiation pressure, the crowded environment and the expected minimum separation for fragmentation being many times greater than the orbital separation.…
The chemical composition of the most metal-deficient stars reflects the composition of the gas from which they formed. These old stars provide crucial clues to the star formation history and the synthesis of chemical elements in the early…
Massive stars influence their surroundings through radiation, winds, and supernova explosions far out of proportion to their small numbers. However, the physical processes that initiate and govern the birth of massive stars remain poorly…
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…
Big Bang nucleosynthesis produces only light elements and the very first generation stars are thus formed from metal-free clouds. They start the production of heavy elements during their life, and enrich the interstellar medium through…
We probe the astrophysical gravitational-wave background resulting from compact binary coalescences, focusing on Population III binary black holes. We exploit results of state-of-the-art simulations on the evolution of Population I-II and…
The first stars in the universe ionized the ambient primordial gas through various feedback processes. "Second-generation" primordial stars potentially form from this disturbed gas after its recombination. In this Letter, we study the late…
The recent gravitational wave merger event, GW190521, has challenged our understanding of the stellar-mass black hole (BH) formation. The primary and secondary BH are both inferred to fall inside the pair-instability (PI) mass gap. Here we…
In this contribution we review our recent numerical work discussing the essential role of the local cluster environment in assembling massive stars. First we show that massive stars are formed from low mass pre-stellar cores and become…
The first stars are thought to be one of the dominant sources of hydrogen reionization in the early Universe, with their high luminosities and surface temperatures expected to drive high ionizing photon production rates. In this work, we…
We calculate numerically the collapse of slowly rotating, non-magnetic, massive molecular clumps, which conceivably could lead to the formation of massive stars. Because radiative acceleration on dust grains plays a critical role in the…
By definition, Population III stars are metal-free, and their protostellar collapse is driven by molecular hydrogen cooling in the gas-phase, leading to large characteristic masses. Population II stars with lower characteristic masses form…
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,…
Collisions were suggested to potentially play a role in the formation of massive stars in present day clusters, and have likely been relevant during the formation of massive stars and intermediate mass black holes within the first star…
We discuss the link between dark matter halos hosting the first PopIII stars and the rare, massive, halos that are generally considered to host bright quasars at high redshift z~6. The main question that we intend to answer is whether the…