Formation and Disruption of Cosmological Low Mass Objects

Abstract

We investigate the evolution of cosmological low mass (low virial temperature) objects and the formation of the first luminous objects. First, the `cooling diagram' for low mass objects is shown. We assess the cooling rate taking into account the contribution of H_2, which is not in chemical equilibrium generally, with a simple argument of time scales. The reaction rates and the cooling rate of H_2 are taken from the recent results by Galli & Palla (1998). Using this cooling diagram, we also estimate the formation condition of luminous objects taking into account the supernova (SN) disruption of virialized clouds. We find that the mass of the first luminous object is several times 10^7 solar mass, because smaller objects may be disrupted by the SNe before they become luminous. Metal pollution of low mass (Ly-alpha) clouds also discussed. The resultant metallicity of the clouds is about 1/1000 of the solar metallicity.

11 pages, 2 figures, To appear in ApJL

Cited by in corpus (37)

• The First Cosmic Structures and their Effects
• The Mass Spectrum of the First Stars
• Is HE0107-5240 A Primordial Star? -- The Characteristics of Extremely Metal-Poor Carbon-Rich Stars --
• Formation of Dwarf Galaxies during the Cosmic Reionization
• Escape of Ionizing Radiation from High-Redshift Galaxies
• The Formation of the First Stars in the Universe
• Effects of dust grains on early galaxy evolution
• Fragmentation and the formation of primordial protostars: the possible role of Collision Induced Emission
• The mass of first stars
• On the photodissociation of H2 by the first stars
• Radiation from the first forming stars
• Cosmological Implications of the Uncertainty in H- Destruction Rate Coefficients
• Merge or survive: Number of Population III stars per minihalo
• Where are the Low-Mass Population III Stars ?
• Criteria for the Formation of Population III Objects in the Ultraviolet Background Radiation
• The First Generation of Star-Forming Haloes
• Low-Mass Star Formation, Triggered by Supernova in Primordial Clouds
• Gravitational Waves Signals from the Collapse of the First Stars
• Starbursts in low-mass haloes at Cosmic Dawn. I. The critical halo mass for star formation
• Formation History of Metal-Poor Halo Stars with Hierarchical Model and the Effect of ISM accretion on the Most Metal-Poor Stars
• Self-Regulation of Star Formation in Low Metallicity Clouds
• Collapse of Low Mass Clouds in the Presence of UV Radiation Field
• Amplification of turbulence in contracting prestellar cores in primordial minihalos
• Formation Criteria and the Mass of Secondary Population III Stars
• UV regulated star formation in high-redshift galaxies
• First supernovae in dwarf protogalaxies
• Quasar Mesolensing - Direct Probe to Substructures around Galaxies -
• Modelling Population III stars for semi-numerical simulations
• Feedback Effects of First Supernovae on the Neighboring Dark Matter Halos
• Stellar mass dependence of the 21-cm signal around the first star and its impact on the global signal
• Amplification and saturation of turbulent magnetic field in collapsing primordial gas clouds
• Extremely Metal-Poor Stars and a Hierarchical Chemical Evolution Model
• Turbulent Compressibilty of Protogalactic Gas
• Saturation level of turbulence in collapsing gas clouds
• Absorption Measurement of Hydrogen Molecules in the Early Universe
• Merger Conditions of Population III Protostar Binaries
• On the Formation Age of the First Planetary System