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Related papers: Clouds as Turbulent Density Fluctuations. Implicat…

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Massive galaxy clusters are filled with a hot, turbulent and magnetized intra-cluster medium. Still forming under the action of gravitational instability, they grow in mass by accretion of supersonic flows. These flows partially dissipate…

Cosmology and Nongalactic Astrophysics · Physics 2015-07-09 Francesco Miniati , Andrey Beresnyak

We present a comprehensive study of MHD waves and instabilities in a weakly ionised system, e.g., an interstellar molecular cloud. We determine all the critical wavelengths of perturbations across which the sustainable wave modes can change…

Solar and Stellar Astrophysics · Physics 2011-04-01 Telemachos Ch. Mouschovias , Glenn E. Ciolek , S. A. Morton

We present a self-consistent hydrodynamical simulation of a Milky Way-like galaxy, at the resolution of 0.05 pc. The model includes star formation and a new implementation of stellar feedback through photo-ionization, radiative pressure and…

Astrophysics of Galaxies · Physics 2015-06-16 F. Renaud , F. Bournaud , E. Emsellem , B. Elmegreen , R. Teyssier , J. Alves , D. Chapon , F. Combes , A. Dekel , J. Gabor , P. Hennebelle , K. Kraljic

We study the linear evolution of small perturbations in self-gravitating fluid systems in two spatial dimensions; we consider both cylindrical and cartesian (i.e., slab) geometries. The treatment is general, but the application is to…

Astrophysics · Physics 2009-10-28 Curtis S. Gehman , Fred C. Adams , Marco Fatuzzo , Richard Watkins

The complexity of the ISM is such that it is unlikely that star formation is initiated in the same way in all molecular clouds. While some clouds seem to collapse on their own, others may be triggered by an external event such as a…

Astrophysics of Galaxies · Physics 2015-05-27 A. Duarte-Cabral , C. L. Dobbs , N. Peretto , G. A. Fuller

Momentum deposition by radiation pressure from young, massive stars may help to destroy molecular clouds and unbind stellar clusters by driving large-scale outflows. We extend our previous numerical radiation hydrodynamic study of…

Astrophysics of Galaxies · Physics 2017-12-06 Sudhir Raskutti , Eve C. Ostriker , M. Aaron Skinner

The condensation of diffuse gas into molecular clouds occurs at a rate driven largely by turbulent dissipation. This process still has to be caught in action and characterized. A mosaic of 13 fields was observed in the CO(1-0) line with the…

Astrophysics of Galaxies · Physics 2015-05-14 E. Falgarone , J. Pety , P. Hily-Blant

The interstellar medium (ISM) provides a unique laboratory for highly supersonic, driven hydrodynamics turbulence. We present a theory of such turbulence, confirm it by numerical simulations, and use the results to explain observational…

Astrophysics · Physics 2008-11-26 Stanislav Boldyrev , Aake Nordlund , Paolo Padoan

The injection and evolution of turbulence in the intergalactic medium is studied by means of mesh-based hydrodynamical simulations, including a subgrid scale (SGS) model for small-scale unresolved turbulence. The simulations show that the…

Cosmology and Nongalactic Astrophysics · Physics 2011-10-03 L. Iapichino , W. Schmidt , J. C. Niemeyer , J. Merklein

We analyse the results of four simulations of isolated galaxies: two with a rigid spiral potential of fixed pattern speed, but with different degrees of star-formation induced feedback, one with an axisymmetric galactic potential and one…

Astrophysics of Galaxies · Physics 2015-06-05 C. L. Dobbs , J. E. Pringle , A. Burkert

In recent years, there were studies on the omnipresence and structures of filaments in star-forming regions, and the role of their fragmentation in the process of star formation. However, only a few studies analysed the evolution of…

Astrophysics of Galaxies · Physics 2018-06-07 Roxana-Adela Chira

We performed simulations of self-gravitating hydrodynamic turbulence to model the formation of filaments, clumps and cores in molecular clouds. We find that when the mass on the initial computational grid is comparable to the Jeans mass,…

Astrophysics · Physics 2007-05-23 David A. Tilley , Ralph E. Pudritz , James Wadsley

Under the basic assumption that the observed turbulent motions in molecular clouds are Alfvenic waves or turbulence, we emphasize that the Doppler broadening of molecular line profiles directly measures the velocity amplitudes of the waves…

Astrophysics · Physics 2009-10-28 Taoling Xie

We study the statistics of density for supersonic turbulence in a medium with magnetic pressure larger than the gaseous pressure. This study is motivated by molecular cloud research. Our simulations exhibit clumpy density structures, which…

Astrophysics · Physics 2009-11-10 A. Beresnyak , A. Lazarian , J. Cho

We examine the effects of self-gravity and magnetic fields on supersonic turbulence in isothermal molecular clouds with high resolution simulations and adaptive mesh refinement. These simulations use large root grids (512^3) to capture…

Solar and Stellar Astrophysics · Physics 2015-06-04 David Collins , Alexei G. Kritsuk , Paolo Padoan , Hui Li , Hao Xu , Sergey D. Ustyugov , Michael L. Norman

To investigate how molecular clouds react to different environmental conditions at a galactic scale, we present a catalogue of giant molecular clouds resolved down to masses of $\sim 10$~M$_{\odot}$ from a simulation of the entire disc of…

How molecular clouds fragment and create the dense structures which go on to form stars is an open question. We investigate the relative importance of different energy terms (kinetic, thermal, magnetic, and gravity - both self-gravity and…

Astrophysics of Galaxies · Physics 2022-04-07 S. Ganguly , S. Walch , S. D. Clarke , D. Seifried

It has been suggested that star-forming galaxies may host a substantial, dark reservoir of gas in the form of planetary-mass molecular clouds that are so cold that $\text{H}_{2}$ can condense. Here we investigate the process of tidal…

Astrophysics of Galaxies · Physics 2025-04-01 Arthur G. Suvorov , Mark A. Walker

The isothermal dynamical evolution of a clumpy and turbulent molecular cloud region and its fragmentation into a protostellar cluster is investigated numerically. The effect of different initial density and velocity distributions, generated…

Astrophysics · Physics 2008-11-26 Ralf S. Klessen , Andreas Burkert

We examine the linear stability of a filamentary cloud permeated by a perpendicular magnetic field. The initial magnetic field is assumed to be uniform and perpendicular to the cloud axis. The model cloud is assumed to have a Plummer-like…

Astrophysics of Galaxies · Physics 2019-09-04 Tomoyuki Hanawa , Takahiro Kudoh , Kohji Tomisaka