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Related papers: The First Galaxies: Assembly, Cooling and the Onse…

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The process of star formation from metal-free gas is investigated by following the evolution of accreting protostars with emphasis on the properties of massive objects. The main aim is to establish the physical processes that determine the…

Astrophysics · Physics 2008-11-26 K. Omukai , F. Palla

Population III stars are the first stars in the Universe to form at z=20-30 out of a pure hydrogen and helium gas in minihalos of 10^5-10^6 M$_\odot$ . Cooling and fragmentation is thus regulated via molecular hydrogen. At densities above…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-16 S. Bovino , D. R. G. Schleicher , T. Grassi

We simulate the formation of a metal-poor (10^-2 Zsun) stellar cluster in one of the first galaxies to form in the early Universe, specifically a high-redshift atomic cooling halo (z~14). This is the first calculation that resolves the…

Astrophysics of Galaxies · Physics 2014-06-19 Chalence Safranek-Shrader , Milos Milosavljevic , Volker Bromm

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…

Astrophysics of Galaxies · Physics 2020-01-22 Bhaskar Agarwal

Thermal regime of the baryons behind shock waves arising in the process of virialization of dark matter halos is governed at cetrain conditions by radiation of HD lines. A small fraction of the shocked gas can cool down to the temperature…

Astrophysics · Physics 2011-08-31 E. O. Vasiliev , Yu. A. Shchekinov

We discuss a possible delay experienced by protogalaxies with low column density of gas in forming stars over large scales. After the hydrogen has recombined, as the external ionizing UV flux decreases and the metal abundance $Z$ increases,…

Astrophysics · Physics 2009-10-28 Edvige Corbelli , Edwin E. Salpeter

High redshift quasars emit copious X-ray photons which heat the intergalactic medium to temperatures up to $\sim$ 10$^6$ K. At such high temperatures the primordial gas will not form stars until it is assembled into dark matter haloes with…

Astrophysics of Galaxies · Physics 2019-07-10 Jarrett L. Johnson , Aycin Aykutalp

We observe a sharp transition from a singular, high-mass mode of star formation, to a low-mass dominated mode, in numerical simulations, at a metallicity of 10^-3 Zsolar. We incorporate a new method for including the radiative cooling from…

Astrophysics · Physics 2009-11-13 Britton D. Smith , Steinn Sigurdsson

First galaxies formed within halos of mass M=E7.5-E9 Msun at z=30-40 in the standard cold dark matter (CDM) universe may each display an extended hydrogen 21-cm absorption halo against the cosmic microwave background with a brightness…

Astrophysics · Physics 2008-11-26 Renyue Cen

Using a recently-developed technique to estimate gas temperatures ($T_\textrm{SF}$) in star-forming regions from large photometric surveys, we propose a diagram, analogous to the Hertzsprung-Russell diagram for individual stars, to probe…

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…

Astrophysics · Physics 2009-07-09 Jonathan Mackey , Volker Bromm , Lars Hernquist

We perform a three dimensional radiation hydrodynamics simulation to investigate the formation of first stars from initial collapse of a primordial gas cloud to formation and growth of protostars. The simulation is integrated until 0.1 Myrs…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-15 Hajime Susa

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…

Astrophysics of Galaxies · Physics 2018-03-14 Shingo Hirano , Naoki Yoshida , Yuya Sakurai , Michiko S. Fujii

Initial conditions for star formation in clusters are estimated for protostars whose masses follow the initial mass function (IMF) from 0.05 to 10 solar masses. Star-forming infall is assumed equally likely to stop at any moment, due to gas…

Astrophysics of Galaxies · Physics 2015-05-18 Philip C. Myers

The James Webb Space Telescope (JWST) will enable observations of galaxies at redshifts z > 10 and hence allow to test our current understanding of structure formation at very early times. Previous work has shown that the very first…

Cosmology and Nongalactic Astrophysics · Physics 2011-05-10 Andreas H. Pawlik , Milos Milosavljevic , Volker Bromm

We conduct a comprehensive theoretical and numerical investigation of the pollution of pristine gas in turbulent flows, designed to provide new tools for modeling the evolution of the first generation of stars. The properties of such…

Astrophysics of Galaxies · Physics 2015-06-16 Liubin Pan , Evan Scannapieco , John Scalo

The gas in galaxy clusters is heated by shock compression through accretion (outer shocks) and mergers (inner shocks). These processes additionally produce turbulence. To analyse the relation between the thermal and turbulent energies of…

Cosmology and Nongalactic Astrophysics · Physics 2016-04-06 Wolfram Schmidt , Jan F. Engels , Jens C. Niemeyer , Ann S. Almgren

Understanding the formation of the first stars and galaxies is a key problem in modern cosmology. In these lecture notes, we will derive some of the basic physical principles underlying this emerging field. We will consider the basic…

Cosmology and Nongalactic Astrophysics · Physics 2012-03-20 Volker Bromm

We use 30 high-resolution dark matter halos of the $Caterpillar$ simulation suite to probe the first stars and galaxies of Milky Way-mass systems. We quantify the environment of the high-$z$ progenitors of the Milky Way and connect them to…

Astrophysics of Galaxies · Physics 2018-01-17 Brendan F. Griffen , Gregory A. Dooley , Alexander P. Ji , Brian W. O'Shea , Facundo A. Gómez , Anna Frebel

We studied the formation process of star clusters using high-resolution N-body/smoothed particle hydrodynamcs simulations of colliding galaxies. The total number of particles is 1.2x10^8 for our high resolution run. The gravitational…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 Takayuki R. Saitoh , Hiroshi Daisaka , Eiichiro Kokubo , Junichiro Makino , Takashi Okamoto , Kohji Tomisaka , Keiichi Wada , Naoki Yoshida
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