Related papers: Collapse of Primordial Clouds
We study the formation of first molecules, negative Hydrogen ions and molecular ions in model of the Universe with cosmological constant and cold dark matter. The cosmological recombination is described in the framework of modified model of…
We have performed two-dimensional hydrodynamic simulations of the collapse of isolated axisymmetric clouds condensing via radiative cooling in a primordial background gas. In order to study the development of the so-called…
We perform a set of cosmological simulations of early structure formation with incorporating baryonic streaming motions. We present a case where a significantly elongated gas cloud with $\sim\!10^4\,$solar masses (${\rm M_\odot}$) is formed…
Collapse and fragmentation of uniform filamentary clouds under isotropic far-ultraviolet external radiation are investigated. Especially, impact of photodissociation of hydrogen molecules during collapse is investigated. Dynamical and…
We study the formation of Pop III stars by performing radiation hydrodynamics simulations for three different initial clouds extracted from cosmological hydrodynamics simulations. Starting from the cloud collapse stage, we follow the growth…
The study of primordial chemistry of molecules adresses a number of interesting questions pertaining to the thermal balance of collapsing molecular protoclouds. In numerous astrophysical cases molecular cooling and heating influence…
We study the formation of molecular hydrogen in cooling gas behind shocks produced during the blow-away process thought to occur in the first collapsed, luminous (Pop III) objects in the early universe. We find that for a wide range of…
This study investigates the influence of Herbig-Haro jets on initiating star formation in dense environments. When molecular clouds are nearing gravitational instability, the impact of a protostellar jet could provide the impetus needed to…
Population III stars were the first generation of stars, formed in minihalos of roughly primordial element abundances, and therefore metal-free. They are thought to have formed at the cores of dense dark matter clouds. Interactions between…
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 have studied the chemistry of nitrogen--bearing species during the initial stages of protostellar collapse, with a view to explaining the observed longevity of N2H+ and NH3 and the high levels of deuteration of these species. We followed…
We calculate the evolution of zero-metallicity Population III (Pop III) stars whose mass grows from the initial mass of $\sim 1M_{\odot}$ by accreting the surrounding gases. Our calculations cover a whole evolutionary stages from the…
The first stars to form in the Universe -- the so-called Population III stars -- bring an end to the cosmological Dark Ages, and exert an important influence on the formation of subsequent generations of stars and on the assembly of the…
We present numerical simulations of primordial supernovae in cosmological minihalos at $z \sim$ 20. We consider Type II supernovae, hypernovae, and pair instability supernovae (PISN) in halos from 6.9 $\times$ 10$^5$ - 1.2 $\times$ 10$^7$…
We briefly review the motivations for studying the formation of the first ``Population III'' stars and present recent results from our numerical simulations in this area. We discuss the new questions raised as a result of the simulations…
Primordial star formation appears to result in stars at least an order of magnitude more massive than modern star formation. It has been proposed that the transition from primordial to modern initial mass functions occurs due to the onset…
(Abridged) We present numerical hydrodynamical simulations of the formation, evolution and gravitational collapse of isothermal molecular cloud cores. A compressive wave is set up in a constant sub-Jeans density distribution of radius r = 1…
Cold dark matter model predicts that the large-scale structure grows hierarchically. Small dark matter halos form first. Then, they grow gradually via continuous merger and accretion. These halos host the majority of baryonic matter in the…
We analyze hierarchical structure formation based on scale-free initial conditions in an Einstein-de Sitter universe, including a baryonic component. We present three independent, smoothed particle hydrodynamics (SPH) simulations, performed…
With the aim of clarifying the nature of the supernova events from stars having initial (at the main sequence) masses larger than $\sim 8$-$10\,M_{\odot}$, we have developed a specifically tailored radiation hydrodynamics Lagrangian code,…