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Related papers: Star formation at high redshift

200 papers

We use simple analytic reasoning to identify physical processes that drive the evolution of the cosmic star formation density in cold dark matter universes. Based on our analysis, we formulate a model to characterise the redshift dependence…

Astrophysics · Physics 2009-07-09 Lars Hernquist , Volker Springel

We study the influence of low levels of metal enrichment on the cooling and collapse of ionized gas in small protogalactic halos using three-dimensional, smoothed particle hydrodynamics simulations. Our initial conditions represent…

Astrophysics · Physics 2008-11-26 A. -K. Jappsen , S. C. O. Glover , R. S. Klessen , M. -M. Mac Low

I present here the main results of recent realistic, 3D, hydrodynamical simulations of convection at the surface of metal-poor red giant stars. I discuss the application of these convection simulations as time-dependent, 3D, hydrodynamical…

Astrophysics · Physics 2009-11-13 R. Collet

We investigate the star formation and chemical evolution in the early universe by considering the merging history of the Galaxy in the {\Lambda}CDM scenario according to the extended Press-Schechter theory. We give some possible constraints…

Astrophysics of Galaxies · Physics 2015-05-19 Yutaka Komiya , Asao Habe , Takuma Suda , Masayuki Y. Fujimoto

We present a simplified chemical and thermal model designed to allow computationally efficient study of the thermal evolution of metal-poor gas within large numerical simulations. Our main simplification is the neglect of the molecular…

Astrophysics · Physics 2009-06-23 S. C. O. Glover , A. -K. Jappsen

We investigate the differential effects of metal cooling and galactic stellar winds on the cosmological formation of individual galaxies with three sets of cosmological, hydrodynamical zoom simulations of 45 halos in the mass range…

Observations of molecular clouds in metal-poor environments typically find that they have much higher star formation rates than one would expect based on their observed CO luminosities and the molecular gas masses that are inferred from…

Astrophysics of Galaxies · Physics 2015-06-04 Simon C. O. Glover , Paul C. Clark

We present a series of hydrodynamic simulations of isolated galaxies with stellar mass of $10^{9} \, \rm{M}_{\odot}$. The models use a resolution of $750 \, \rm{M}_{\odot}$ per particle and include a treatment for the full non-equilibrium…

Astrophysics of Galaxies · Physics 2016-02-17 Alexander J. Richings , Joop Schaye

We present preliminary results of stellar structure and nucleosynthesis calculations for some early stars. The study (still in progress) seeks to explore the expected chemical signatures of second generation low- and intermediate-mass stars…

Astrophysics · Physics 2007-05-23 S. W. Campbell

Star formation is regulated through a variety of feedback processes. In this study, we treat feedback by metal injection and a UV background as well as by X-ray irradiation. Our aim is to investigate whether star formation is significantly…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 Marco Spaans , Aycin Aykutalp , Seyit Hocuk

The formation of the first stars out of metal-free gas appears to result in stars at least an order of magnitude more massive than in the present-day case. We here consider what controls the transition from a primordial to a modern initial…

Astrophysics · Physics 2011-02-11 A. -K. Jappsen , M. -M. Mac Low , S. C. O. Glover , R. S. Klessen , S. Kitsionas

We present a novel scenario for the formation of carbon-enhanced metal-poor (CEMP) stars. Carbon enhancement at low stellar metallicities is usually considered a consequence of faint or other exotic supernovae. An analytical estimate of…

Astrophysics of Galaxies · Physics 2019-01-09 Tilman Hartwig , Naoki Yoshida

We make use of new subgrid model of turbulent mixing to accurately follow the cosmological evolution of the first stars, the mixing of their supernova ejecta, and the impact on the chemical composition of the Galactic Halo. Using the…

Astrophysics of Galaxies · Physics 2017-01-04 Richard Sarmento , Evan Scannapieco , Liubin Pan

We study star cluster formation in various environments with different metallicities and column densities by performing a suite of three-dimensional radiation hydrodynamics simulations. We find that the photoionization feedback from massive…

Astrophysics of Galaxies · Physics 2020-08-25 Hajime Fukushima , Hidenobu Yajima , Kazuyuki Sugimura , Takashi Hosokawa , Kazuyuki Omukai , Tomoaki Matsumoto

We revisit the formation and evolution of the first galaxies using new hydrodynamic cosmological simulations with the ART code. Our simulations feature a recently developed model for H2 formation and dissociation, and a star formation…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 Alexander L. Muratov , Oleg Y. Gnedin , Nickolay Y. Gnedin , Marcel Zemp

We investigate the process of self-regulated star formation via photodissociation of hydrogen molecules in low metallicity clouds. We evaluate the influence region's scale of a massive star in low metallicity gas clouds whose temperatures…

Astrophysics · Physics 2009-10-31 Ryoichi Nishi , Motomichi Tashiro

We examine how the atomic and molecular gas components of galaxies evolve to higher redshifts using the semi-analytic galaxy formation models of Fu et al. (2010) in which we track the surface density profiles of gas in disks. We adopt two…

Astrophysics of Galaxies · Physics 2015-06-04 Jian Fu , Guinevere Kauffmann , Cheng Li , Qi Guo

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…

Properties of candidate stars, forming out of molecular clouds, depend on the ambient conditions of the parent cloud. We present a series of 2D and 3D simulations of fragmentation of molecular clouds in starburst regions as well as clouds…

Solar and Stellar Astrophysics · Physics 2014-11-20 S. Hocuk , M. Spaans

The theory for the formation of the first population of stars (Pop III) predicts an initial mass function (IMF) dominated by high-mass stars, in contrast to the present-day IMF, which tends to yield mostly stars with masses less than 1…

Solar and Stellar Astrophysics · Physics 2016-02-17 Gustavo Dopcke , Simon C. O. Glover , Paul C. Clark , Ralf S. Klessen