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Related papers: Nature of supersonic turbulence and density distri…

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Turbulent gas motions are observed in the intracluster medium (ICM). The ICM is density-stratified, with the gas density being highest at the centre of the cluster and decreasing radially outwards. As a result of this, Kolmogorov…

Astrophysics of Galaxies · Physics 2020-12-04 Rajsekhar Mohapatra , Christoph Federrath , Prateek Sharma

Star formation is primarily controlled by the interplay between gravity, turbulence, and magnetic fields. However, the turbulence and magnetic fields in molecular clouds near the Galactic Center may differ substantially from spiral-arm…

Magnetic fields grow quickly, even at early cosmological times, suggesting the action of a small-scale dynamo (SSD) in the interstellar medium (ISM) of galaxies. Many studies have focused on idealized, isotropic, homogeneous, turbulent…

Astrophysics of Galaxies · Physics 2023-02-15 Frederick A. Gent , Mordecai-Mark Mac Low , Maarit J. Korpi-Lagg , Nishant K. Singh

We use three-dimensional simulations to study the statistics of supersonic turbulence in molecular clouds. Our numerical experiments describe driven turbulent flows with an isothermal equation of state, Mach numbers around 10, and various…

Astrophysics of Galaxies · Physics 2009-05-18 Alexei G. Kritsuk , Sergey D. Ustyugov , Michael L. Norman , Paolo Padoan

We study the dynamics of phase transitions in the interstellar medium by means of three-dimensional hydrodynamic numerical simulations. We use a realistic cooling function and generic nonequilibrium initial conditions to follow the…

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

We examine the physical parameters that affect the accumulation of gas in molecular clouds to high column densities where the formation of stars takes place. In particular, we analyze the dense gas mass fraction (DGMF) in a set of…

Astrophysics of Galaxies · Physics 2015-06-15 Jouni Kainulainen , Christoph Federrath , Thomas Henning

Shocks form the basis of our understanding for the density and velocity statistics of supersonic turbulent flows, such as those found in the cool interstellar medium (ISM). The variance of the density field, $\sigma^2_{\rho/\rho_0}$, is of…

Astrophysics of Galaxies · Physics 2021-04-28 James R. Beattie , Philip Mocz , Christoph Federrath , Ralf S. Klessen

This paper investigates the statistical properties of isothermal turbulence in both the subsonic and supersonic regimes. The focus is on the influence of the Mach number ($Ma$) and the Reynolds number ($Re$) on both the space-local and…

Fluid Dynamics · Physics 2025-10-16 F. Thiesset , C. Federrath

The supernova-driven interstellar medium in star-forming galaxies has Reynolds numbers of the order of $10^{6}$ or even larger. We study, by means of adaptive mesh refinement hydro- and magnetohydrodynamical simulations that cover the full…

Astrophysics · Physics 2007-05-23 M. A. de Avillez , D. Breitschwerdt

(Abridged) We discuss the nonlinear development of the isobaric mode of thermal instability (TI) in the context of the atomic interstellar medium (ISM), in order to assess the ability of TI to establish a well-segregated multi-phase…

Astrophysics · Physics 2009-11-07 F. J. Sanchez-Salcedo , E. Vazquez-Semadeni , A. Gazol

We examine observational characteristics of multi-phase turbulent flows in the diffuse interstellar medium (ISM) using a synthetic radiation field of atomic and molecular lines. We consider the multi-phase ISM which is formed by thermal…

Astrophysics · Physics 2008-11-26 M. Yamada , H. Koyama , K. Omukai , S. Inutsuka

Turbulent fragmentation determines where and when protostellar cores form, and how they contract and grow in mass from the surrounding cloud material. This process is investigated, using numerical models of self-gravitating molecular cloud…

Astrophysics · Physics 2010-04-06 Ralf Klessen

The ISM is a turbulent, multi-phase, and multi-scale medium following scaling relations. Analytical models of galactic gaseous disks need to take into account the multi-scale and multi-phase nature of the interstellar medium. They can be…

Astrophysics of Galaxies · Physics 2022-07-27 T. Lizée , B. Vollmer , J. Braine , P. Gratier , F. Bigiel

In a systematic study, we compare the density statistics in high resolution numerical experiments of supersonic isothermal turbulence, driven by the usually adopted solenoidal (divergence-free) forcing and by compressive (curl-free)…

Astrophysics · Physics 2009-02-25 Christoph Federrath , Ralf S. Klessen , Wolfram Schmidt

It has recently been shown that turbulence in the interstellar medium (ISM) can significantly accelerate the growth of dust grains by accretion of molecules, but the turbulent gas-density distribution also plays a crucial role in shaping…

Astrophysics of Galaxies · Physics 2020-10-09 Lars Mattsson

As a first step to a more complete understanding of the local physical processes which determine star formation rates (SFRs) in the interstellar medium (ISM), we have performed controlled numerical experiments consisting of hydrodynamical…

Astrophysics · Physics 2009-11-10 A. Slyz , J. Devriendt , Greg Bryan , Joseph Silk

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

Formation of interstellar clouds as a consequence of thermal instability is studied using two-dimensional two-fluid magnetohydrodynamic simulations. We consider the situation of converging, supersonic flows of warm neutral medium in the…

Astrophysics of Galaxies · Physics 2015-05-14 Tsuyoshi Inoue , Shu-ichiro Inutsuka

We review recent advances in the analytical and numerical modeling of the star formation rate in molecular clouds and discuss the available observational constraints. We focus on molecular clouds as the fundamental star formation sites,…

Context: The gas density structure of the cold molecular phase of the interstellar medium is the main controller of star formation. Aims: A theoretical framework is proposed to describe the structural content of the density field in…

Fluid Dynamics · Physics 2023-08-15 Fabien Thiesset , Christoph Federrath