Cradles of the first stars: self-shielding, halo masses, and multiplicity

Abstract

The formation of Population III (Pop III) stars is a critical step in the evolution of the early universe. To understand how these stars affected their metal-enriched descendants, the details of how, why and where Pop III formation takes place needs to be determined. One of the processes that is assumed to greatly affect the formation of Pop III stars is the presence of a Lyman-Werner (LW) radiation background, that destroys H${}_2$, a necessary coolant in the creation of Pop III stars. Self-shielding can alleviate the effect the LW background has on the H${}_2$ within haloes. In this work, we perform a cosmological simulation to study the birthplaces of Pop III stars, using the adaptive mesh refinement code Enzo. We investigate the distribution of host halo masses and its relationship to the LW background intensity. Compared to previous work, haloes form Pop III stars at much lower masses, up to a factor of a few, due to the inclusion of H${}_2$ self-shielding. We see no relationship between the LW intensity and host halo mass. Most haloes form multiple Pop III stars, with a median number of four, up to a maximum of 16, at the instance of Pop III formation. Our results suggest that Pop III star formation may be less affected by LW radiation feedback than previously thought and that Pop III multiple systems are common.

Accepted in MNRAS

References in corpus (18)

• The Formation of Population III Binaries from Cosmological Initial Conditions
• Primordial Star Formation under the Influence of Far Ultraviolet Radiation: 1540 Cosmological Halos and the Stellar Mass Distribution
• The Mass Spectrum of the First Stars
• Fragmentation of star-forming clouds enriched with the first dust
• Resolving the Formation of Protogalaxies. III. Feedback from the First Stars
• Population III star formation in a Lambda CDM universe, I: The effect of formation redshift and environment on protostellar accretion rate
• Population III star formation in a Lambda CDM universe, II: Effects of a photodissociating background
• Formation of massive black holes in rapidly growing pre-galactic gas clouds
• The Birth of a Galaxy. II. The Role of Radiation Pressure
• Suppression of H_2 Cooling in the Ultraviolet Background
• Supersonic Gas Streams Enhance the Formation of Massive Black Holes in the Early Universe
• Metal-Free Gas Supply at the Edge of Reionization: Late-Epoch Population III Star Formation
• Fossils of Reionization in the Local Group
• Recovery from population III supernova explosions and the onset of second generation star formation
• Evidence for an aspherical Population III supernova explosion inferred from the hyper metal-poor star HE1327-2326
• Predicting the locations of possible long-lived low-mass first stars: Importance of satellite dwarf galaxies
• How an improved implementation of H2 self-shielding influences the formation of massive stars and black holes
• Lyman-Werner Escape Fractions from the First Galaxies

Cited by in corpus (18)

• When did Population III star formation end?
• R-Process elements from magnetorotational hypernovae
• Gravitational wave of intermediate-mass black holes in Population III star clusters
• Unveiling the contribution of Pop III stars in primeval galaxies at redshift $\ge 6$
• Machine learning detects multiplicity of the first stars in stellar archaeology data
• Constraining Warm Dark Matter and Pop III stars with the Global 21-cm Signal
• Population III X-ray Binaries and their Impact on the Early Universe
• Seeding the second star -- II. CEMP star formation enriched from faint supernovae
• From dark matter halos to pre-stellar cores: High resolution follow-up of cosmological Lyman-Werner simulations
• A-SLOTH reveals the nature of the first stars
• Tracing stars in Milky Way satellites with A-SLOTH
• Can Population III stars be major origins of both merging binary black holes and extremely metal poor stars?
• A Metal-Free Galaxy at $z=3.19$? Evidence of Late Population III Star Formation at Cosmic Noon
• The Impact of Molecular Hydrogen Cooling on the Galaxy Formation Threshold
• Lessons on early structure formation from a mature galaxy cluster observed at cosmic noon
• Radiation magnetohydrodynamics simulations of Population III star formation during the Epoch of Reionization
• Revealing the formation histories of the first stars with the cosmic near-infrared background
• The Baryon Budget of Galaxies across the First Billion Years