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Related papers: Statistics of Centroids of Velocity

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We use the results of magnetohydrodynamic (MHD) simulations to emulate spectroscopic observations and use maps of centroids to study their statistics. In order to assess under which circumstances the scaling properties of the velocity field…

Astrophysics · Physics 2007-05-23 A. Esquivel , A. Lazarian

The investigation of the statistical properties of maps of line centroids has been used for almost 50 years, but there is still no general agreement on their interpretation. We try to quantify which properties of underlying turbulent…

Astrophysics · Physics 2009-11-11 V. Ossenkopf , A. Esquivel , A. Lazarian , J. Stutzki

We study possibility of obtaining velocity spectra by studying turbulence in an optically thick medium using velocity centroids (VCs).We find that the regime of universal, i.e. independent of underlying turbulence statistics, fluctuations…

Astrophysics of Galaxies · Physics 2016-10-12 D. Kandel , A. Lazarian , D. Pogosyan

We address the problem of studying interstellar turbulence using spectral line data. We find a criterion when the velocity centroids may provide trustworthy velocity statistics. To enhance the scope of centroids applications, we construct a…

Astrophysics · Physics 2009-11-07 A. Lazarian , A. Esquivel

We present an analytical study of the statistical properties of integrated emission and velocity centroids for a slightly compressible turbulent slab model, to retrieve the underlying statistics of three-dimensional density and velocity…

Astrophysics · Physics 2009-11-10 F. Levrier

Magnetic turbulence is anisotropic as the directions of motion are constrained by the magnetic field. Such anisotropy can be observed in velocity centroids obtained from spectroscopic observations. We use magnetohydrodynamics (MHD)…

Astrophysics of Galaxies · Physics 2020-08-13 D. Hernández-Padilla , A. Esquivel , A. Lazarian , D. Pogosyan , D. Kandel , J. Cho

Turbulence is a crucial component of dynamics of astrophysical fluids dynamics, including those of ISM, clusters of galaxies and circumstellar regions. Doppler shifted spectral lines provide a unique source of information on turbulent…

Astrophysics · Physics 2016-01-27 A. Lazarian

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

Velocity statistics is a direct probe of the dynamics of interstellar turbulence. Its observational measurements are very challenging due to the convolution between density and velocity and projection effects. We introduce the projected…

Astrophysics of Galaxies · Physics 2020-01-08 Siyao Xu

Turbulence is a crucial component of dynamics of astrophysical fluids dynamics, including those of ISM, clusters of galaxies and circumstellar regions. Doppler shifted spectral lines provide a unique source of information on turbulent…

Astrophysics · Physics 2007-05-23 A. Lazarian

We use a set of magnetohydrodynamics (MHD) simulations of fully-developed (driven) turbulence to study the anisotropy in the velocity field that is induced by the presence of the magnetic field. In our models we study turbulence…

Astrophysics of Galaxies · Physics 2015-05-30 Alejandro Esquivel , Alex Lazarian

The dynamics of the interstellar medium (ISM) are strongly affected by turbulence, which shows increased anisotropy in the presence of a magnetic field. We expand upon the Esquivel & Lazarian method to estimate the Alfven Mach number using…

Astrophysics of Galaxies · Physics 2015-06-22 Blakesley Burkhart , A. Lazarian , I. C. Leao , J. R. de Medeiros , A. Esquivel

Turbulence is a key element of the dynamics of astrophysical fluids, including those of interstellar medium, clusters of galaxies and circumstellar regions. Turbulent motions induce Doppler shifts of observable emission and absorption lines…

Astrophysics · Physics 2009-03-27 A. Chepurnov , A. Lazarian

In a previous work Lazarian and Pogosyan suggested a technique to extract velocity and density statistics, of interstellar turbulence, by means of analysing statistics of spectral line data cubes. In this paper we test that technique, by…

Astrophysics · Physics 2009-11-07 Alejandro Esquivel , A. Lazarian , D. Pogosyan , Jungyeon Cho

The complex interplay between turbulence, magnetic fields, and self-gravity leads to the formation of molecular clouds out of the diffuse interstellar medium (ISM). One avenue of studying this interplay is by analyzing statistical features…

Astrophysics of Galaxies · Physics 2017-02-22 Frank Otto , Weiguang Ji , Hua-bai Li

Energy dissipation rate is an important parameter for nearly every experiment on turbulent flow. Mathematically precise relationships between energy dissipation rate and other measurable statistics for the case of anisotropic turbulence are…

Fluid Dynamics · Physics 2008-02-28 Reginald J. Hill

Emission in spectral lines can provide unique information on interstellar turbulence. Doppler shifts due to supersonic motions contain information on turbulent velocity field which is otherwise difficult to measure. However, the problem of…

Astrophysics · Physics 2016-08-30 A. Lazarian

HI data cubes are sources of unique information on interstellar turbulence. Doppler shifts due to supersonic motions contain information on turbulent velocity field which is otherwise difficult to obtain. However, the problem of separation…

Astrophysics · Physics 2007-05-23 A. Lazarian , D. Pogosyan , Alejandro Esquivel

Turbulence is a key element of the dynamics of astrophysical fluids, including those of interstellar medium, clusters of galaxies and circumstellar regions. Turbulent motions induce Doppler shifts of observable emission and absorption…

Astrophysics · Physics 2010-12-13 A. Lazarian

The advancement of our understanding of MHD turbulence opens ways to develop new techniques to probe magnetic fields. In MHD turbulence, the velocity gradients are expected to be perpendicular to magnetic fields and this fact was used by…

Astrophysics of Galaxies · Physics 2017-03-15 Ka Ho Yuen , A. Lazarian
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