English
Related papers

Related papers: Extragalactic Synchrotron Sources at Low Frequenci…

200 papers

It has recently become apparent that the background level of diffuse radio emission on the sky is significantly higher than the level that can result from known extragalactic radio source classes or our Galaxy given our current…

Cosmology and Nongalactic Astrophysics · Physics 2019-12-02 J. Singal

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 limited angular resolutions and sensitivities historically available below 300 MHz have made it difficult to define the low end of the electron energy distribution, N(gamma). We extrapolate down from the well observed segments of radio…

Astrophysics · Physics 2007-05-23 D. E. Harris

In recent years, the level of the extragalactic radio background has become a point of considerable interest, with some lines of argument pointing to an entirely new cosmological synchrotron background. The contribution of the known…

Cosmology and Nongalactic Astrophysics · Physics 2020-11-18 M. J. Hardcastle , T. W. Shimwell , C. Tasse , P. N. Best , A. Drabent , M. J. Jarvis , I. Prandoni , H. J. A. Rottgering , J. Sabater , D. J. Schwarz

In the framework of the study of extragalactic radio sources, we will focus on the importance of the spatial resolution at different wavelengths, and of the combination of observations at different frequency bands. In particular, a…

Astrophysics · Physics 2009-09-29 Gianfranco Brunetti

The low-frequency radio sky is dominated by the diffuse synchrotron emission of our Galaxy and extragalactic radio sources related to Active Galactic Nuclei and star-forming galaxies. This foreground emission is much brighter than the…

Cosmology and Nongalactic Astrophysics · Physics 2019-09-30 Emma Chapman , Vibor Jelić

BL Lacertae objects are extreme extragalactic sources characterized by the emission of strong and rapidly variable nonthermal radiation over the entire electromagnetic spectrum. Synchrotron emission followed by inverse Compton scattering in…

Astrophysics · Physics 2009-10-31 P. Giommi , G. Ghisellini , P. Padovani , G. Tagliaferri

For over four decades, synchrotron-radiating sources have played a series of pathfinding roles in the study of galaxy clusters and large scale structure. Such sources are uniquely sensitive to the turbulence and shock structures of…

Gravitational wave detectors in space, particularly the LISA project, can study a rich variety of astronomical systems whose gravitational radiation is not detectable from the ground, because it is emitted in the low-frequency gravitational…

General Relativity and Quantum Cosmology · Physics 2007-05-23 B. F. Schutz

A brief summary of some highlights in the study of high energy astrophysical sources over the past decade is presented. It is argued that the great progress that has been made derives largely from the application of new technology to…

Astrophysics · Physics 2007-05-23 R. D. Blandford

We present historical VLA and Jansky Very Large Array multi-frequency multi-array radio continuum imaging of a unique sample of 100 radio sources that have been selected on the basis of low axial ratios. These observations allow us the…

Despite an intense theoretical and experimental effort over the past decade, observations of the extragalactic radio background at multiple frequencies below 10 GHz are not understood in terms of known radio sources, and may represent a…

High Energy Physics - Phenomenology · Physics 2023-08-02 Andrea Caputo , Hongwan Liu , Siddharth Mishra-Sharma , Maxim Pospelov , Joshua T. Ruderman

Gravitational waves (GWs) at ultra-low frequencies (${\lesssim 100\,\mathrm{nHz}}$) are key to understanding the assembly and evolution of astrophysical black hole (BH) binaries with masses $\sim 10^{6}-10^{9}\,M_\odot$ at low redshifts.…

Cosmology and Nongalactic Astrophysics · Physics 2021-10-26 Christopher J. Moore , Alberto Vecchio

Astrophysical sources emit gravitational waves in a large variety of processes occurred since the beginning of star and galaxy formation. These waves permeate our high redshift Universe, and form a background which is the result of the…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 Raffaella Schneider , Stefania Marassi , Valeria Ferrari

Galactic synchrotron emission is a potentially confusing foreground, both in total power and in polarization, to the Cosmic Microwave Background Radiation. It also contains much physical information in its own right. This review examines…

Astrophysics · Physics 2007-05-23 R. D. Davies , A. Wilkinson

Determining the energy spectrum of an electron population can give key insights into the underlying physics of a radio source; however, the lack of high resolution, broad-bandwidth observations has left many ambiguities in our understanding…

Astrophysics of Galaxies · Physics 2014-05-01 J. J. Harwood , M. J. Hardcastle , J. H. Croston , A. Stroe , R. Morganti , E. Orru

Inhomogeneities can influence the polarisation emerging from a synchrotron source. However, it is shown that the frequency distribution of circular polarisation is only marginally affected, although its magnitude may change substantially.…

High Energy Astrophysical Phenomena · Physics 2020-05-13 C. -I. Bjornsson

It is well established that particle acceleration by shocks and turbulence in the intra-cluster medium can produce cluster-scale synchrotron emitting sources. However, the detailed physics of these particle acceleration processes is still…

We aim to present a tutorial on the detection, parameter estimation and statistical analysis of compact sources (far galaxies, galaxy clusters and Galactic dense emission regions) in cosmic microwave background observations. The topic is of…

Cosmology and Nongalactic Astrophysics · Physics 2011-01-05 D. Herranz , P. Vielva

Models for the diffuse Galactic continuum emission and synchrotron radiation show that it is difficult to reproduce observations of both of these from the same population of cosmic-ray electrons. This indicates that an important contributor…

Astrophysics · Physics 2009-10-31 A. W. Strong , I. V. Moskalenko
‹ Prev 1 2 3 10 Next ›