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Related papers: Galactic Magnetic Turbulence from Radio data

200 papers

We derive an expression for the angular power spectrum of cosmic microwave background anisotropies due to gravity waves generated by a stochastic magnetic field and compare the result with current observations; we take into account the…

Astrophysics · Physics 2016-08-30 R. Durrer , P. G. Ferreira , T. Kahniashvili

When magnetohydrodynamic turbulence evolves in the presence of a large-scale mean magnetic field, an anisotropy develops relative to that preferred direction. The well-known tendency is to develop stronger gradients perpendicular to the…

Plasma Physics · Physics 2020-07-15 Rohit Chhiber , William H. Matthaeus , Sean Oughton , Tulasi N. Parashar

High energy electrons and positrons from annihilating dark matter can imprint unique angular anisotropies on the diffuse gamma-ray flux by inverse Compton scattering off the interstellar radiation field. We develop a numerical tool to…

High Energy Astrophysical Phenomena · Physics 2011-02-10 Le Zhang , Francesco Miniati , Guenter Sigl

Galactic cosmic ray transport relies on the existence of turbulence on scales comparable with the gyration radius of the particles and with wavenumber vector oriented along the local magnetic field. In the standard picture, in which…

High Energy Astrophysical Phenomena · Physics 2023-12-29 O. Pezzi , P. Blasi

We show that the large-scale cosmic ray anisotropy at ~10 TeV can be explained by a modified Compton-Getting effect in the magnetized flow field of old supernova remnants. This approach suggests an optimum energy scale for detecting the…

High Energy Astrophysical Phenomena · Physics 2015-06-05 P. L. Biermann , J. K. Becker , E. -S. Seo , M. Mandelartz

Theoretical approaches to low-frequency magnetized turbulence in collisionless and weakly collisional astrophysical plasmas are reviewed. The proper starting point for an analytical description of these plasmas is kinetic theory, not fluid…

Astrophysics · Physics 2009-11-11 A. A. Schekochihin , S. C. Cowley , W. Dorland

Using results of numerical simulations and astrophysical observations (mainly in the WMAP and Planck frequency bands) it is shown that Galactic foreground emission becomes more sensitive to the mean magnetic field with the frequency, that…

Astrophysics of Galaxies · Physics 2025-06-04 A. Bershadskii

Aims: We study the Galactic large-scale synchrotron emission by generating a reliable all-sky spectral index map and temperature map at 45 MHz. Methods: We use our observations, the published all-sky map at 408 MHz, and a bibliographical…

Astrophysics of Galaxies · Physics 2010-12-10 Andres E. Guzmán , Jorge May , Hector Alvarez , Koitiro Maeda

We present the first targeted measurement of the power spectrum of anisotropies of the radio synchrotron background, at 140 MHz where it is the overwhelmingly dominant photon background. This measurement is important for understanding the…

Cosmology and Nongalactic Astrophysics · Physics 2023-07-06 A. R. Offringa , J. Singal , S. Heston , S. Horiuchi , D. M. Lucero

We investigate the spectral shape, the anisotropy of the wave vector distributions and the anisotropy of the amplitudes of the magnetic fluctuations in the Earth's magnetosheath within a broad range of frequencies. We present the first…

Astrophysics · Physics 2015-05-13 Olga Alexandrova , Catherine Lacombe , Andre Mangeney

An inhomogeneous cosmological magnetic field creates vortical perturbations that survive Silk damping on much smaller scales than compressional modes. This ensures that there is no sharp cut-off in anisotropy on arc-minute scales. As we had…

Astrophysics · Physics 2009-11-07 Kandaswamy Subramanian , John D. Barrow

Recent measurements of the Cosmic Microwave Background Anisotropy have provided evidence for the presence of oscillations in the angular power spectrum. These oscillations are a wonderful confirmation of the standard cosmological scenario…

Astrophysics · Physics 2007-05-23 Alessandro Melchiorri

We aim to explore whether strong magnetic fields can be effectively generated in low-mass dwarf galaxies and, if so, whether such fields can be affected by galactic outflows and spread out into the intergalactic medium (IGM). We performed a…

Astrophysics of Galaxies · Physics 2016-03-16 Krzysztof T. Chyzy , Robert T. Drzazga , Rainer Beck , Marek Urbanik , Volker Heesen , Dominik J. Bomans

The distribution of arrival directions of cosmic rays is remarkably isotropic, which is a consequence of their repeated scattering in magnetic fields. Yet, high-statistics observatories like IceCube and HAWC have revealed the presence of…

High Energy Astrophysical Phenomena · Physics 2019-12-04 Philipp Mertsch , Markus Ahlers

We present an extensive analysis on the determination of the isotropic radio background. We consider six different radio maps, ranging from 22 MHz to 2.3 GHz and covering a large fraction of the sky. The large scale emission is modeled as a…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-18 Nicolao Fornengo , Roberto A. Lineros , Marco Regis , Marco Taoso

Synchrotron emission is an important process in Galactic dynamics and a potentially confusing foreground for cosmic microwave background (CMB) radiation observations. Though the mechanism of synchrotron emission is well understood, the…

Astrophysics · Physics 2007-05-23 George F. Smoot

The emission from the relativistically hot plasmas of high-energy astrophysical synchrotron sources, pulsar wind nebulae (PWNe) in particular, depends on the level of magnetic fluctuations. Recent observations by the X-ray polarimeter IXPE…

High Energy Astrophysical Phenomena · Physics 2025-10-22 Luca Del Zanna , Niccolò Bucciantini , Simone Landi

We introduce a novel diffusion model for the propagation of cosmic rays (CRs) that incorporates an anisotropic diffusion tensor of a general form within a realistically modeled large-scale Galactic magnetic field. The parameters of the…

High Energy Astrophysical Phenomena · Physics 2025-07-22 V. D. Borisov , V. O. Yurovsky , I. A. Kudryashov

Interstellar synchrotron emission depends on Galactic magnetic fields and on cosmic-ray leptons. Observations of radio emission are an important tool for studying cosmic-ray propagation models and interstellar electron spectrum and…

Astrophysics of Galaxies · Physics 2013-07-24 Elena Orlando , Andrew W. Strong

Low energy galactic cosmic rays as well as particles accelerated to high energies either at the solar surface or in the interplanetary medium have access to the atmosphere above a given position on the Earth depending upon the state of the…

Earth and Planetary Astrophysics · Physics 2013-03-19 K. Kudela , R. Bucik