English
Related papers

Related papers: Non-gaussian probability distribution functions in…

200 papers

We study the quasilinear evolution of the one-point probability density functions (PDFs) of the smoothed density and velocity fields in a cosmological gravitating system beginning with Gaussian initial fluctuations. Our analytic results are…

Astrophysics · Physics 2009-10-22 Lev Kofman , Edmund Bertschinger , James M. Gelb , Adi Nusser , Avishai Dekel

Statistical properties of the interplanetary magnetic field fluctuations can provide an important insight into the solar wind turbulent cascade. Recently, analysis of the Probability Density Functions (PDF) of the velocity and magnetic…

Astrophysics · Physics 2015-06-24 Bogdan Hnat , Sandra Chapman , George Rowlands , Nicholas Watkins , William Farrell

We introduce the position-dependent probability distribution function (PDF) of the smoothed matter field as a cosmological observable. In comparison to the PDF itself, the spatial variation of the position-dependent PDF is simpler to model…

Cosmology and Nongalactic Astrophysics · Physics 2021-04-29 Drew Jamieson , Marilena Loverde

In magnetohydrodynamic (MHD) turbulence, the large-scale magnetic field sets a preferred local direction for the small-scale dynamics, altering the statistics of turbulence from the isotropic case. This happens even in the absence of a…

Plasma Physics · Physics 2017-05-10 Vladimir Zhdankin , Stanislav Boldyrev , Joanne Mason

We analyze particle velocity fluctuations in a simulated granular system subjected to homogeneous quasistatic shearing. We show that these fluctuations share the following scaling characteristics of fluid turbulence in spite of their…

Soft Condensed Matter · Physics 2009-11-07 F. Radjai , S. Roux

In probability density function (PDF) methods of turbulent flows, the joint PDF of several flow variables is computed by numerically integrating a system of stochastic differential equations for Lagrangian particles. A mathematically exact…

Fluid Dynamics · Physics 2010-06-17 J. Bakosi

We perform a detailed analytical study of the Recent Fluid Deformation (RFD) model for the onset of Lagrangian intermittency, within the context of the Martin-Siggia-Rose-Janssen-de Dominicis (MSRJD) path integral formalism. The model is…

Fluid Dynamics · Physics 2018-10-10 G. B. Apolinário , L. Moriconi , R. M. Pereira

We study the effect of density fluctuations induced by turbulence on the HI/H$_2$ structure in photodissociation regions (PDRs) both analytically and numerically. We perform magnetohydrodynamic numerical simulations for both subsonic and…

Astrophysics of Galaxies · Physics 2017-07-26 Shmuel Bialy , Blakesley Burkhart , Amiel Sternberg

Intermittent fluctuations in the boundary of magnetically confined plasmas are investigated by numerical turbulence simulations of a reduced fluid model describing the evolution of the plasma density and electric drift vorticity in the…

We use the multifractal formalism to describe the effects of dissipation on Lagrangian velocity statistics in turbulent flows. We analyze high Reynolds number experiments and direct numerical simulation (DNS) data. We show that this…

Statistical Mechanics · Physics 2007-05-23 L. Chevillard , S. G. Roux , E. Leveque , N. Mordant , J. -F. Pinton , A. Arneodo

We study experimentally the statistical properties and evolution of circulation in a turbulent flow passing through a smooth 2-D contraction. The turbulence is generated with an active grids to reach $Re_{\lambda} \simeq 220$ at the inlet…

Fluid Dynamics · Physics 2024-01-31 Vivek Mugundhan , Sigurdur T. Thoroddsen

Recent measurements of solar wind turbulence report the presence of intermittent, exponentially distributed angular discontinuities in the magnetic field. In this Letter, we study whether such discontinuities can be produced by…

Solar and Stellar Astrophysics · Physics 2012-10-15 Vladimir Zhdankin , Stanislav Boldyrev , Joanne Mason , Jean Carlos Perez

This paper demonstrates that intermittent magnetic field fluctuations in the plasma sheet exhibit transitory, localized, and multi-scale features. We propose a multifractal based algorithm, which quantifies intermittence on the basis of the…

The scaling properties of oil price fluctuations are described as a non-stationary stochastic process realized by a time series of finite length. An original model is used to extract the scaling exponent of the fluctuation functions within…

Statistical Finance · Quantitative Finance 2008-12-02 M. Momeni , I. Kourakis , K. Talebi

A fluctuation law of the energy in freely-decaying, homogeneous and isotropic turbulence is derived within standard closure hypotheses for 3D incompressible flow. In particular, a fluctuation-dissipation relation is derived which relates…

chao-dyn · Physics 2009-10-28 Gregory L. Eyink

We present the first study of the multiscaling of time-dependent velocity and magnetic-field structure functions in homogeneous, isotropic magnetohydrodynamic (MHD) turbulence in three dimensions. We generalize the formalism that has been…

Fluid Dynamics · Physics 2016-11-08 Samriddhi Sankar Ray , Ganapati Sahoo , Rahul Pandit

The probability distribution function (PDF) of the mass surface density is an essential characteristic of the structure of molecular clouds or the interstellar medium in general. Observations of the PDF of molecular clouds indicate a…

Astrophysics of Galaxies · Physics 2015-06-18 Joerg Fischera

Magnetic field fluctuations in the vicinity of the Earth's bow shock have been investigated with the aim to characterize the intermittent behaviour of strong plasma turbulence. The observed small-scale intermittency may be the signature of…

comp-gas · Physics 2020-01-29 T. Dudok de Wit , V. V. Krasnosel'skikh

We investigate the scaling behavior of longitudinal and transverse structure functions in homogeneous and isotropic magneto-hydrodynamic (MHD) turbulence by means of an exact hierarchy of structure function equations as well as by direct…

Fluid Dynamics · Physics 2017-05-03 J. Friedrich , H. Homann , T. Schäfer , R. Grauer

Direct numerical simulations of decaying and forced magnetohydrodynamic (MHD) turbulence without and with mean magnetic field are analyzed by higher-order two-point statistics. The turbulence exhibits statistical anisotropy with respect to…

Plasma Physics · Physics 2009-11-10 Wolf-Christian Mueller , Dieter Biskamp , Roland Grappin