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Related papers: Driven Multifluid MHD Molecular Cloud Turbulence

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Most observed stars are part of a multiple star system, but the formation of such systems and the role of environment and various physical processes is still poorly understood. We present a suite of radiation-magnetohydrodynamic simulations…

Turbulence plays a critical role in regulating star formation in molecular clouds and is also observed in simulations of primordial halos that host Population III (Pop III) stars. The relative velocity between baryons and dark matter at the…

The transport of heavy, neutral or charged, point-like particles by incompressible, resistive magnetohydrodynamic (MHD) turbulence is investigated by means of high-resolution numerical simulations. The spatial distribution of such…

Fluid Dynamics · Physics 2015-05-13 H. Homann , J. Bec , H. Fichtner , R. Grauer

The chemistry of molecular clouds has been studied for decades, with an increasingly general and sophisticated treatment of the reactions involved. Yet the treatment of turbulent diffusion has remained extremely sketchy, assuming simple…

Astrophysics · Physics 2009-06-23 G. Marschalko , K. Petrovay , E. Forgacs-Dajka

Firstly, we give a historical overview of attempts to incorporate magnetic fields into the Smoothed Particle Hydrodynamics method by solving the equations of Magnetohydrodynamics (MHD), leading an honest assessment of the current…

Astrophysics of Galaxies · Physics 2015-05-20 Daniel J. Price

{It is well established that the atomic interstellar hydrogen is filling the galaxies and constitutes the building blocks of molecular clouds.} {To understand the formation and the evolution of molecular clouds, it is necessary to…

Astrophysics of Galaxies · Physics 2015-05-14 E. Audit , P. Hennebelle

We briefly review helicity dynamics, inverse and bi-directional cascades in fluid and magnetohydrodynamic (MHD) turbulence, with an emphasis on the latter. The energy of a turbulent system, an invariant in the non-dissipative case, is…

Fluid Dynamics · Physics 2019-03-13 A. Pouquet , D. Rosenberg , J. E. Stawarz , R. Marino

We investigate particle acceleration in an MHD-scale system of multiple current sheets by performing 2D and 3D MHD simulations combined with a test particle simulation. The system is unstable for the tearing-mode instability, and magnetic…

Space Physics · Physics 2022-08-16 M. Nakanotani , G. P. Zank , L. -L. Zhao

We address the problem of the difference of line widths of neutrals and ions observed from molecular clouds and explore whether this difference can arise from the effects of magnetohydrodynamic (MHD) turbulence acting on partially ionized…

Astrophysics of Galaxies · Physics 2015-09-09 Siyao Xu , A. Lazarian , Huirong Yan

The interaction of a shock with a cloud has been extensively studied in the literature, where the effects of magnetic fields, radiative cooling and thermal conduction have been considered. However, the formation of fully developed…

Astrophysics · Physics 2009-11-13 J. M. Pittard , S. A. E. G. Falle , T. W. Hartquist , J. E. Dyson

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

We use 3D numerical MHD simulations to follow the evolution of cold, turbulent, gaseous systems with parameters representing GMC conditions. We study three cloud simulations with varying mean magnetic fields, but identical initial velocity…

Astrophysics · Physics 2008-11-26 Eve C. Ostriker , James M. Stone , Charles F. Gammie

Galaxies comprise intricate networks of interdependent processes which together govern their evolution. Central among these are the multiplicity of feedback channels, which remain incompletely understood. One outstanding problem is the…

Astrophysics of Galaxies · Physics 2023-12-11 Brent Tan , Drummond B. Fielding

Externally driven interstellar turbulence plays an important role in shaping the density structure in molecular clouds. Here we study the dynamical role of internally driven turbulence in a self-gravitating molecular cloud core. Depending…

Astrophysics of Galaxies · Physics 2020-03-04 Siyao Xu , Alex Lazarian

Radiative turbulent mixing layers are expected to form pervasively at the phase boundaries in multiphase astrophysical systems. This inherently small scale structure is dynamically crucial because it directly regulates the mass, momentum…

Astrophysics of Galaxies · Physics 2023-10-04 Xihui Zhao , Xue-Ning Bai

The effect of turbulence on the heterogeneous (solid-fluid) reactions of solid particles is studied numerically with Direct Numerical Simulations (DNS). A simplified reaction system is used, where the solid-fluid reaction is represented by…

Fluid Dynamics · Physics 2016-07-14 Jonas Krüger , Nils E. L. Haugen , Dhrubaditya Mitra , Terese Løvås

Giant Molecular Clouds (GMCs) are observed to be turbulent, but theory shows that without a driving mechanism turbulence should quickly decay. The question arises by which mechanisms turbulence is driven or sustained. It has been shown that…

Astrophysics of Galaxies · Physics 2014-12-01 D. M. Boneberg , J. E. Dale , P. Girichidis , B. Ercolano

We propose that inward, subsonic flows arise from the local dissipation of turbulent motions in molecular clouds. Such "turbulent cooling flows" may account for recent observations of spatially extended inward motions towards dense cores.…

Astrophysics · Physics 2009-10-31 P. Myers , A. Lazarian

We perform numerical magnetohydrodynamic (MHD) simulations of the gravitational collapse and fragmentation of a cylindrical molecular cloud with the help of the FLASH code. The cloud collapses rapidly along its radius without any signs of…

Astrophysics of Galaxies · Physics 2024-05-15 I. M. Sultanov , S. A. Khaibrakhmanov

We study the dynamics of large, charged dust grains in turbulent giant molecular clouds (GMCs). Massive dust grains behave as aerodynamic particles in primarily neutral dense gas, and thus are able to produce dramatic small-scale…

Astrophysics of Galaxies · Physics 2017-07-11 Hyunseok Lee , Philip F. Hopkins , Jonathan Squire