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The interstellar scintillation observed in radio pulsars arises from interference between electromagnetic waves scattered by electron density fluctuations in the turbulent interstellar plasma, providing a critical tool for probing the…

Type III radio bursts are a signature of the flux of near-relativistic electrons ejected during solar flares. These bursts are frequently observed by spacecraft such as the Parker Solar Probe. It is traditionally believed that these…

The propagation of light that undergoes multiple-scattering by resonant atomic vapor can be described as a L\'evy flight. L\'evy flight is a random walk with heavy tailed step-size (r) distribution, decaying asymptotically as $P(r)\sim…

In the inflationary universe scenario, the physical wavelength of cosmological fluctuation modes which are currently probed in observations was shorter than the Hubble radius, and in fact shorter than the Planck and string lengths, at the…

High Energy Physics - Theory · Physics 2007-05-23 Paul Robert Chouha , Robert H. Brandenberger

We study the emission of large-scales wavelength space-time waves during the inflationary expansion of the universe, produced by back-reaction effects. As an example, we study an inflationary model with variable time scale, where the scale…

General Relativity and Quantum Cosmology · Physics 2020-06-12 Juan Ignacio Musmarra , Mauricio Bellini

The statistics of Lagrangian pair dispersion in a homogeneous isotropic flow is investigated by means of direct numerical simulations. The focus is on deviations from Richardson eddy-diffusivity model and in particular on the strong…

Fluid Dynamics · Physics 2015-06-11 Rehab Bitane , Holger Homann , Jeremie Bec

Variations of dispersion measure (DM) have been observed in some binary pulsars, which can not be well explained by the propagation effects, such as turbulence of the interstellar media (ISM) between the Earth and the pulsar. This paper…

Astrophysics · Physics 2007-05-23 B. P. Gong

The paper presents a multidimensional model for nonlinear Markovian random walks that generalizes one we developed previously (Phys. Rev. E v.79, 011110, 2009) in order to describe the Levy type stochastic processes in terms of continuous…

Statistical Mechanics · Physics 2015-05-13 Ihor Lubashevsky , Rudolf Friedrich , Andreas Heuer

Using linear kinetic plasma theory the relation between electron density and magnetic field fluctuations for low-frequency plasma waves for Maxwellian background distribution functions of arbitrary temperatures in an uniform magnetic field…

Astrophysics · Physics 2007-05-23 R. Schlickeiser , I. Lerche

The problem of the origin of cosmic rays in the shocks produced by supernova explosions at energies below the so called 'knee' (at ~3*10$^6$ GeV) in the energy spectrum is addressed, with special attention to the propagation of the…

Astrophysics · Physics 2008-11-26 A. D. Erlykin , A. A. Lagutin , A. W. Wolfendale

Radio pulsars scintillate because their emission travels through the ionized interstellar medium via multiple paths, which interfere with each other. It has long been realized that the scattering screens responsible for the scintillation…

High Energy Astrophysical Phenomena · Physics 2018-05-25 Robert Main , I-Sheng Yang , Victor Chan , Dongzi Li , Fang Xi Lin , Nikhil Mahajan , Ue-Li Pen , Keith Vanderlinde , Marten H. van Kerkwijk

The Parkes telescope has been monitoring 286 radio pulsars approximately monthly since 2007 at an observing frequency of 1.4 GHz. The wide dispersion measure (DM) range of the pulsar sample and the uniformity of the observing procedure make…

High Energy Astrophysical Phenomena · Physics 2021-01-06 H. Kumamoto , S. Dai , S. Johnston , M. Kerr , R. M. Shannon , P. Weltevrede , C. Sobey , R. N. Manchester , G. Hobbs , K. Takahashi

Large-scale structures, observed today, are generally believed to have grown from random, small-amplitude inhomogeneities, present in the early Universe. We investigate how gravitational instability drives the distribution of these…

Astrophysics · Physics 2009-10-22 R. Juszkiewicz , F. R. Bouchet , S. Colombi

During reionization, a fraction of galactic Ly$\alpha$ emission is scattered in the intergalactic medium (IGM) and appears as a diffuse light extending megaparsecs from the source. We investigate how to probe the properties of the early…

Cosmology and Nongalactic Astrophysics · Physics 2022-06-08 Hyunbae Park , Hyo Jeong Kim , Kyungjin Ahn , Hyunmi Song , Intae Jung , Pierre Ocvirk , Paul R. Shapiro , Taha Dawoodbhoy , Jenny G. Sorce , Ilian T. Iliev

We derive all contributions to the dispersion measure (DM) of electromagnetic pulses to linear order in cosmological perturbations, including both density fluctuations and relativistic effects. We then use this result to calculate the power…

Cosmology and Nongalactic Astrophysics · Physics 2021-06-30 David Alonso

We study experimentally the particle velocity fluctuations in an electrostatically driven dilute granular gas. The experimentally obtained velocity distribution functions have strong deviations from Maxwellian form in a wide range of…

Statistical Mechanics · Physics 2016-08-31 I. S. Aranson , J. S. Olafsen

This paper is devoted to a statistical analysis of the fluctuations of velocity and acceleration produced by a random distribution of point vortices in two-dimensional turbulence. We show that the velocity probability density function…

Statistical Mechanics · Physics 2009-10-31 Pierre-Henri Chavanis , Clément Sire

Finite-time Lyapunov exponents of generic chaotic dynamical systems fluctuate in time. These fluctuations are due to the different degree of stability across the accessible phase-space. A recent numerical study of spatially-extended systems…

Chaotic Dynamics · Physics 2013-12-02 Diego Pazó , Juan M. López , Antonio Politi

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

Velocity distributions in a vibrated granular monolayer are investigated experimentally. Non-Gaussian velocity distributions are observed at low vibration amplitudes but cross over smoothly to Gaussian distributions as the amplitude is…

Soft Condensed Matter · Physics 2009-10-31 J. S. Olafsen , J. S. Urbach