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Related papers: Star formation at high redshift

200 papers

We present first results of an implementation of chemical evolution in a cosmological hydrodynamical code, focusing the analysis on the effects of cooling baryons according to their metallicity. We found that simulations with primordial…

Astrophysics · Physics 2007-05-23 Patricia B. Tissera , Cecilia Scannapieco

In this work, we study the chemical compositions and kinematic properties of six metal-poor stars with [Fe/H] $< -2.5$ in the Galactic halo. From high-resolution (R $\sim$~110,000) spectroscopic observations obtained with the Lick/APF, we…

Astrophysics of Galaxies · Physics 2019-09-04 Mohammad K. Mardini , Vinicius M. Placco , Ali Taani , Haining Li , Gang Zhao

By definition, Population III stars are metal-free, and their protostellar collapse is driven by molecular hydrogen cooling in the gas-phase, leading to large characteristic masses. Population II stars with lower characteristic masses form…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 John H. Wise , Matthew J. Turk , Michael L. Norman , Tom Abel

A brief review concludes that there is now good overall agreement between theoretical estimates of the energy associated with the production of the observed metal content of the Universe and the observed extragalactic background light. In…

Astrophysics · Physics 2007-05-23 Simon J. Lilly , C. Marcella Carollo , Alan N. Stockton

The gas-phase metallicity affects heating and cooling processes in the star-forming galactic interstellar medium (ISM) as well as ionising luminosities, wind strengths, and lifetimes of massive stars. To investigate its impact, we conduct…

The theory for the formation of the first population of stars (Pop III) predicts a IMF composed predominantly of high-mass stars, in contrast to the present-day IMF, which tends to yield stars with masses less than 1 M_Solar. The leading…

Astrophysics of Galaxies · Physics 2015-05-27 Gustavo Dopcke , Simon C. O. Glover , Paul C. Clark , Ralf S. Klessen

The formation of molecular clouds out of HI gas is the first step toward star formation. Its metallicity dependence plays a key role to determine star formation through the cosmic history. Previous theoretical studies with detailed chemical…

Astrophysics of Galaxies · Physics 2023-08-29 Masato I. N. Kobayashi , Kazunari Iwasaki , Kengo Tomida , Tsuyoshi Inoue , Kazuyuki Omukai , Kazuki Tokuda

The first stars in the universe, termed Population III, are thought to have been very massive compared to the stars that form in the present epoch. As feedback from the first generation of stars altered the contents of the interstellar…

Solar and Stellar Astrophysics · Physics 2014-03-24 Gregory R. Meece , Britton D. Smith , Brian W. O'Shea

The collapse of dense cores with different metallicities is studied by hydrodynamical calculations coupled with detailed chemical and radiative processes. For this purpose, we construct a simple chemical network with non-equilibrium…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 Kazuyuki Omukai , Takashi Hosokawa , Naoki Yoshida

We implemented Population III (Pop. III) star formation in mini-halos within the MERAXES semi-analytic galaxy formation and reionisation model, run on top of a N-body simulation with $L = 10 h^{-1}$ cMpc with 2048$^3$ particles resolving…

Astrophysics of Galaxies · Physics 2024-02-22 Emanuele M. Ventura , Yuxiang Qin , Sreedhar Balu , J. Stuart B. Wyithe

Recent discoveries of carbon-enhanced metal-poor stars like SMSS J031300.36-670839.3 provide increasing observational insights into the formation conditions of the first second-generation stars in the Universe, reflecting the chemical…

Solar and Stellar Astrophysics · Physics 2015-06-22 S. Bovino , T. Grassi , D. R. G. Schleicher , M. A. Latif

Recent theoretical investigations have suggested that the formation of the very first stars, forming out of metal-free gas, was fundamentally different from the present-day case. In this paper, we study the effect of metallicity on the…

Astrophysics · Physics 2009-11-06 V. Bromm , A. Ferrara , P. S. Coppi , R. B. Larson

The formation of supermassive stars has generally been studied under the assumption of rapid accretion of pristine metal-free gas. Recently it was found, however, that gas enriched to metallicities up to $Z \sim 10^{-3}$ Z$_{\odot}$ can…

Astrophysics of Galaxies · Physics 2020-09-16 John A. Regan , Zoltán Haiman , John H. Wise , Brian W. O'Shea , Michael L. Norman

We report the statistical properties of stars and brown dwarfs obtained from three radiation hydrodynamical simulations of star cluster formation with metallicities of 1, 1/10 and 1/100 of the solar value. The star-forming clouds are…

Solar and Stellar Astrophysics · Physics 2022-11-30 Matthew R. Bate

We study the influence of gas metallicity, turbulence, and non-equilibrium chemistry on the evolution of the two-phase interstellar medium (warm and cold atomic phases), and thereby constrain the initial conditions for star formation…

Astrophysics of Galaxies · Physics 2015-05-27 S. Walch , R. Wuensch , A. Burkert , S. Glover , A. Whitworth

Stars form by the gravitational collapse of interstellar gas. The thermodynamic response of the gas can be characterized by an effective equation of state. It determines how gas heats up or cools as it gets compressed, and hence plays a key…

Employing hydrodynamic simulations of structure formation in a LCDM cosmology, we study the history of cosmic star formation from the "dark ages" at redshift z~20 to the present. In addition to gravity and ordinary hydrodynamics, our model…

Astrophysics · Physics 2009-11-07 Volker Springel , Lars Hernquist

We utilize state-of-the-art 3D hydrodynamical and classical 1D stellar model atmospheres to study the influence of convection on the formation properties of various atomic and molecular spectral lines in the atmospheres of four red giant…

Solar and Stellar Astrophysics · Physics 2013-10-30 V. Dobrovolskas , A. Kučinskas , M. Steffen , H. -G. Ludwig , D. Prakapavičius , J. Klevas , E. Caffau , P. Bonifacio

We present a comprehensive observational study of the gas phase metallicity of star-forming galaxies from z ~ 0 -> 3. We combine our new sample of gravitationally lensed galaxies with existing lensed and non-lensed samples to conduct a…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 T. -T. Yuan , L. J. Kewley , J. Richard

We review theoretical approaches to the study of galaxy formation, with emphasis on the role of hydrodynamic simulations in modeling the high redshift galaxy population. We present new predictions for the abundance of star-forming galaxies…

Astrophysics · Physics 2007-05-23 David H. Weinberg , Romeel Dave' , Jeffrey P. Gardner , Lars Hernquist , Neal Katz