相关论文: The Positive Feedback of Pop III Objects on Galaxy…
We study the effects of the ionizing and dissociating photons produced by Pop III objects on the surrounding intergalactic medium. We find that the typical size of a H_2 photodissociated region is smaller than the mean distance between…
First, the formation of first objects driven by dark matter is revisited by high-resolution hydrodynamic simulations. It is revealed that dark matter haloes of ~10^4M_sun can produce first luminous objects with the aid of dark matter cusps.…
The first billion years in the evolution of the Universe mark the formation of the first stars, black holes and galaxies. The radiation from the first galaxies plays an important role in determining the final state of primordial gas…
We use one-dimensional radiative transfer simulations to study the evolution of H_2 gas-phase (H^- catalyzed) formation and photo-dissociation regions in the primordial universe. We find a new positive feedback mechanism capable of…
We review some of the possible observable effects (reionization, feedback on galaxy formation, supernovae and metal enrichment) of the first collapsed, luminous (Pop III) objects in the universe. We show that supernovae in these objects…
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…
Cosmic structure originated from minute density perturbations in an almost homogeneous universe. The first stars are believed to be very massive and luminous, providing the first ionizing radiation and heavy elements to the universe and…
We explore possibilities of collapse and star formation in Population III objects exposed to the external ultraviolet background (UVB) radiation. Assuming spherical symmetry, we solve self-consistently radiative transfer of photons,…
We explore the formation of secondary Population III (Pop III) stars under radiation hydrodynamic (RHD) feedback by a preformed massive star. To properly treat RHD feedback, we perform three-dimensional RHD simulations incorporating the…
The formation of the first galaxies is influenced by the radiative feedback from the first generations of stars. This feedback is manisfested by the heating and ionization of the gas which lies within the H II regions surrounding the first…
We explore the possibility of subsequent star formation after a first star forms in a Pop III object, by focusing on the radiation hydrodynamic (RHD) feedback brought by ionizing photons as well as H2 dissociating photons. For the purpose,…
We study the effect of starlight from the first stars on the ability of other minihaloes in their neighborhood to form additional stars. The question of what the dynamical consequences were for these target minihaloes, of their exposure to…
Lyman-Werner (LW) radiation photodissociating molecular hydrogen (H$_2$) influences the thermal and dynamical evolution of the Population III (Pop III) star-forming gas cloud. The effect of powerful LW radiation has been well investigated…
We study the effects of the ionizing and dissociating photons produced by PopIII objects on the surrounding intergalactic medium. We find that the typical size of a H_2 photodissociated region, R_d ~ 1-5 kpc, is smaller than the mean…
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…
We describe how star formation is expected to proceed in the early metal-free Universe, focusing on the very first generations of stars. We then discuss how the star formation process may change as the effects of metallicity, external…
The first stars form in dark matter halos of masses ~10^6 M_sun as suggested by an increasing number of numerical simulations. Radiation feedback from these stars expels most of the gas from their shallow potential well of their surrounding…
Molecular hydrogen allows cooling in primordial gas, facilitating its collapse into Population III stars within primordial halos. Lyman-Werner (LW) radiation from these stars can escape the halo and delay further star formation by…
We explore the formation of massive high-redshift Population III (Pop III) galaxies through photoionization feedback. We consider dark matter halos formed from progenitors that have undergone no star formation as a result of early…
We utilize cosmological hydrodynamic simulations to study the formation of Population III (Pop III) stars in dark matter halos exposed to strong ionizing radiation. We simulate the formation of three halos subjected to a wide range of…