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Related papers: Turbulent Compressibilty of Protogalactic Gas

200 papers

Stars form from molecular gas under complex conditions influenced by multiple competing physical mechanisms, such as gravity, turbulence, and magnetic fields. However, accurately identifying the fraction of gas actively involved in star…

Star formation in high-redshift dwarf galaxies is a key to understand early galaxy evolution in the early Universe. Using the three-dimensional hydrodynamics code GIZMO, we study the formation mechanism of cold, high-density gas clouds in…

Astrophysics of Galaxies · Physics 2018-01-31 Shohei Arata , Hidenobu Yajima , Kentaro Nagamine

Stars in galaxies form in giant molecular clouds that coalesce when the atomic hydrogen is converted into molecules. There are currently two dominant models for what property of the galactic disk determines its molecular fraction: either…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 Michele Fumagalli , Mark R. Krumholz , Leslie K. Hunt

This paper reports the first measurement of the relationship between turbulent velocity and cloud size in the diffuse circumgalactic medium (CGM) in typical galaxy halos at redshift z~0.4-1. Through spectrally-resolved absorption profiles…

The thermodynamical evolution of gas during the collapse of the primordial star-forming cloud depends significantly on the initial degree of rotation. However, there is no clear understanding of how the initial rotation can affect the…

Astrophysics of Galaxies · Physics 2015-12-23 Jayanta Dutta

We show that the turbulent gas in the star-forming regions of galaxies is unstable to wind formation via momentum deposition by radiation pressure or other momentum sources like supernova explosions, even if the system is below the average…

Astrophysics of Galaxies · Physics 2015-12-16 Todd A. Thompson , Mark R. Krumholz

We use three-dimensional hydrodynamic numerical simulations to study phase transformations occurring in a clumpy interstellar gas exposed to time-dependent volumetric heating. To mimic conditions in the Galactic interstellar medium, we take…

Astrophysics · Physics 2009-11-07 Alexei G. Kritsuk , Michael L. Norman

In cold dark matter cosmological models, the first stars to form are believed to do so within small protogalaxies. We wish to understand how the evolution of these early protogalaxies changes once the gas forming them has been enriched with…

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

Self-gravitational fluid mechanical methods termed hydro-gravitational-dynamics (HGD) predict plasma fragmentation 0.03 Myr after the turbulent big bang to form protosuperclustervoids, turbulent protosuperclusters, and protogalaxies at the…

Astrophysics · Physics 2008-08-26 Carl H. Gibson , Rudolph E. Schild

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 performed numerical simulations of supersonic isothermal turbulence driven by mostly compressive large-scale forcing, using both a static grid and adaptive mesh refinement with an effective resolution N=768^3. After a transient phase…

The first generation of protogalaxies likely formed out of primordial gas via H2-cooling in cosmological minihalos with virial temperatures of a few 1000K. However, their abundance is likely to have been severely limited by feedback…

Astrophysics · Physics 2009-11-07 S. Peng Oh , Zoltan Haiman

(Abridged). In this paper, we present results from a large set of numerical simulations that demonstrate that H2 formation occurs rapidly in turbulent gas. Starting with purely atomic hydrogen, large quantities of molecular hydrogen can be…

Astrophysics · Physics 2008-11-26 S. C. O. Glover , M. -M. Mac Low

Over the past decade increasingly robust estimates of the dense molecular gas content in galaxy populations between redshift 0 and the peak of cosmic galaxy/star formation from redshift 1-3 have become available. This rapid progress has…

Astrophysics of Galaxies · Physics 2020-11-11 Linda J. Tacconi , Reinhard Genzel , Amiel Sternberg

We propose that turbulent heating, wave pressure and gas exchanges between different regions of disks play a dominant role in determining the preferred, quasi-equilibrium, self-similar states of gas disks on large-scales. We present simple…

Astrophysics · Physics 2009-10-31 Curtis Struck , Daniel C. Smith

Star formation in galaxies is regulated by the heating and cooling in the interstellar medium. In particular, the processing of molecular gas into stars will depend strongly on the ratio of gas heating to gas cooling in the neutral gas…

We report on simulations of the formation of the first stars in the Universe, where we identify regions of hot atomic gas (fH2 < 10-6) at densities above 10-14 g/cc, heated to temperatures ranging between 3000 and 8000 K. Within this…

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

We investigate the structure of galaxies formed in a suite of high-resolution cosmological simulations. Consistent with observations of high-redshift galaxies, our simulated galaxies show irregular, prolate shapes, which are dominated by…

Astrophysics of Galaxies · Physics 2022-08-16 Xi Meng , Oleg Y. Gnedin , Hui Li

The injection of turbulence in the circum-galactic medium at redshift z = 2 is investigated using the mesh-based hydrodynamic code Enzo and a subgrid-scale (SGS) model for unresolved turbulence. Radiative cooling and heating by a uniform…

Cosmology and Nongalactic Astrophysics · Physics 2013-06-18 Luigi Iapichino , Matteo Viel , Stefano Borgani

(Abridged) Galaxies form in hierarchically assembling dark matter halos. With cosmological three dimensional adaptive mesh refinement simulations, we explore in detail the virialization of baryons in the concordance cosmology, including…

Astrophysics · Physics 2009-06-23 John H. Wise , Tom Abel