English
Related papers

Related papers: Statistics of Turbulence from Spectral-Line Data C…

200 papers

We present results from two-dimensional numerical simulations of a supersonic turbulent flow in the plane of the galactic disk, incorporating shear, thresholded and discrete star formation (SF), self-gravity, rotation and magnetic fields. A…

Astrophysics · Physics 2009-10-28 T. Passot , E. Vazquez-Semadeni , A. Pouquet

The physics of turbulence in magnetized plasmas remains an unresolved problem. The most poorly understood aspect is intermittency -- spatio-temporal fluctuations superimposed on the self-similar turbulent motions. We employ a novel…

High Energy Astrophysical Phenomena · Physics 2025-05-21 Trung Ha , Joonas Nättilä , Jordy Davelaar , Lorenzo Sironi

Statistical properties of circulation encode relevant information about the multi-scale structure of turbulent cascades. Recent massive computational efforts have posed challenging theoretical issues, as the dependence of circulation…

Fluid Dynamics · Physics 2020-11-04 G. B. Apolinário , L. Moriconi , R. M. Pereira , V. J. Valadão

We present a direct numerical and analytical study of driven supersonic MHD turbulence that is believed to govern the dynamics of star-forming molecular clouds. We describe statistical properties of the turbulence by measuring the velocity…

Astrophysics · Physics 2009-11-07 Stanislav Boldyrev , Aake Nordlund , Paolo Padoan

Most detected neutral atomic hydrogen (HI) at low redshift is associated with optically bright galaxies. However, a handful of HI clouds are known which appear to be optically dark and have no nearby potential progenitor galaxies, making…

Astrophysics of Galaxies · Physics 2018-05-23 Rhys Taylor , Richard Wünsch , Jan Palouš

We use numerical simulations to investigate effect of turbulent velocity on the power spectrum of \HI intensity from external galaxies when (a) all emission is considered, (b) emission with velocity range smaller than the turbulent velocity…

Astrophysics of Galaxies · Physics 2015-07-16 Prasun Dutta

We compare DNS calculations of homogeneous isotropic turbulence with the statistical properties of intra-cluster turbulence from the Matryoshka Run (Miniati 2014) and find remarkable similarities between their inertial ranges. This allowed…

Cosmology and Nongalactic Astrophysics · Physics 2016-02-02 Andrey Beresnyak , Francesco Miniati

The interstellar turbulence is magnetized and thus anisotropic. The anisotropy of turbulent magnetic fields and velocities is imprinted in the related observables, rotation measures (RMs), and velocity centroids (VCs). This anisotropy…

Astrophysics of Galaxies · Physics 2021-04-07 Siyao Xu , Yue Hu

We provide a theoretical description of synchrotron fluctuations arising from magnetic turbulence. We derive an expression that relates the correlation of synchrotron fluctuations for an arbitrary index of relativistic electrons with the…

Astrophysics of Galaxies · Physics 2015-05-28 Alex Lazarian , Dmitri Pogosyan

The nonlinear dynamics of a bundle of magnetic flux ropes driven by stationary fluid motions at their endpoints is studied, by performing numerical simulations of the magnetohydrodynamic (MHD) equations. The development of MHD turbulence is…

Plasma Physics · Physics 2009-11-10 Pablo Dmitruk , Daniel O. Gomez , William H. Matthaeus

Context. Amongst many plasma processes potentially relevant to the dynamics of the intracluster medium (ICM), turbulence driven at observable scales by internal magnetised buoyancy instabilities like the magneto-thermal instability (MTI)…

High Energy Astrophysical Phenomena · Physics 2024-04-30 Jean M. Kempf , Francois Rincon , Nicolas Clerc

The observational record of turbulence within the molecular gas phase of the interstellar medium is summarized. We briefly review the analysis methods used to recover the velocity structure function from spectroscopic imaging and the…

Astrophysics · Physics 2009-11-11 M. H. Heyer , C. Brunt

Turbulent fluid flows exhibit a complex small-scale structure with frequently occurring extreme velocity gradients. Particles probing such swirling and straining regions respond with an intricate shape-dependent orientational dynamics,…

Fluid Dynamics · Physics 2020-11-30 Leonhard A. Leppin , Michael Wilczek

In this paper we present a novel hydrodynamic experiment using liquid $^4$He. The flow is forced inertially by a canonical oscillating grid using either its normal (He~I) or superfluid (He~II) phase, generating a statistically stationary…

Fluid Dynamics · Physics 2021-06-16 Fatimata Sy , Pantxo Diribarne , Bernard Rousset , Mathieu Gibert , Mickael Bourgoin

Context: Existing SWAS observations and future HIFI/Herschel data require a clear sense of the information content of water emission and absorption lines. Aims: Investigate wether the ground-state transition of ortho-H2O, 1_(10)-1_(01), at…

Astrophysics · Physics 2009-11-11 D. R. Poelman , M. Spaans , A. G. G. M. Tielens

Supersonic turbulence in molecular clouds is a dominant agent that strongly affects the clouds' evolution and star formation activity. Turbulence may be initiated and maintained by a number of processes, acting at a wide range of physical…

Astrophysics of Galaxies · Physics 2014-11-20 C. M. Brunt , M. H. Heyer , M. -M. Mac Low

Solar wind is probably the best laboratory to study turbulence in astrophysical plasmas. In addition to the presence of magnetic field, the differences with neutral fluid isotropic turbulence are: weakness of collisional dissipation and…

Solar and Stellar Astrophysics · Physics 2015-06-16 Olga Alexandrova , Christopher H. K. Chen , Luca Sorriso-Valvo , Timothy S. Horbury , Stuart D. Bale

To study subregions of a turbulence velocity field, a long record of velocity data of grid turbulence is divided into smaller segments. For each segment, we calculate statistics such as the mean rate of energy dissipation and the mean…

Fluid Dynamics · Physics 2009-11-13 H. Mouri , A. Hori , M. Takaoka

The intermittent dissipation of interstellar turbulence is an important energy source in the diffuse ISM. Though on average smaller than the heating rates due to cosmic rays and the photoelectric effect on dust grains, the turbulent cascade…

Astrophysics of Galaxies · Physics 2015-09-11 Andrew Myers , Christopher McKee , Pak Shing Li

In this paper we show results of numerical simulations for the turbulence in the interstellar medium. These results were obtained using a Riemann solver-free numerical scheme for high-Mach number hyperbolic equations. Here we especially…

Astrophysics of Galaxies · Physics 2011-02-11 R. Kissmann , J. Kleimann , H. Fichtner , R. Grauer