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Related papers: The isotropic radio background revisited

200 papers

The detection of a dipole anisotropy in the sky distribution of sources in large-scale radio surveys can be used to constrain the magnitude and direction of our local motion with respect to an isotropically distributed extragalactic radio…

Astrophysics · Physics 2009-11-13 Fronefield Crawford

Notwithstanding the advent of the Gamma-ray Large Area Telescope, theoretical models predict that a significant fraction of the cosmic gamma-ray background (CGB), at the level of 20% of the currently measured value, will remain unresolved.…

Astrophysics · Physics 2009-11-13 Francesco Miniati , Savvas M. Koushiappas , Tiziana Di Matteo

We present high-resolution radio observations of a sample of 65 radio sources at low Galactic latitudes. The sources were all observed at 5 GHz with the Very Large Array A-array. MERLIN observations at 5 GHz of the ultracompact HII region…

Astrophysics · Physics 2009-11-10 D. J. Saikia , P. Thomasson , S. Roy , A. Pedlar , T. W. B. Muxlow

We discuss interpretation of the cosmic infrared background (CIB) anisotropies detected by us recently in the Spitzer IRAC based measurements. The fluctuations are approximately isotropic on the sky consistent with their cosmological…

Astrophysics · Physics 2009-11-11 A. Kashlinsky , R. G. Arendt , J. Mather , S. H. Moseley

Astrophysical radio sources are embedded in turbulent magnetised environments. In the 1 MHz sky, solar radio bursts are the brightest sources, produced by electrons travelling along magnetic field lines from the Sun through the heliosphere.…

We present an improved Global Sky Model (GSM) of diffuse galactic radio emission from 10 MHz to 5 THz, whose uses include foreground modeling for CMB and 21 cm cosmology. Our model improves on past work both algorithmically and by adding…

Cosmology and Nongalactic Astrophysics · Physics 2016-10-05 Haoxuan Zheng , Max Tegmark , Joshua S. Dillon , Doyeon A. Kim , Adrian Liu , Abraham Neben , Justin Jonas , Patricia Reich , Wolfgang Reich

The radio continuum spectra of 14 star-forming galaxies are investigated by fitting nonthermal (synchrotron) and thermal (free-free) radiation laws. The underlying radio continuum measurements cover a frequency range of ~325 MHz to 24.5 GHz…

Astrophysics of Galaxies · Physics 2018-03-28 Uli Klein , Ute Lisenfeld , Simon Verley

Radio continuum surveys of the Galactic plane can find and characterize HII regions, supernova remnants (SNRs), planetary nebulae (PNe), and extragalactic sources. A number of surveys at high angular resolution (<25") at different…

We use the radio-infrared (IR) flux correlation bet ween star-forming galaxies in the local universe to derive a simple analytical expression between the intensity of the IR background and the brightness t emperature of the radio…

Astrophysics · Physics 2009-11-07 Eli Dwek , Michael K. Barker

The effects on CMB measurements of foreground contamination due to synchrotron radiation, free-free emission and discrete sources are considered. Estimates of the level and power spectrum of the Galactic fluctuations are made using low…

Astrophysics · Physics 2007-05-23 A. N. Lasenby

Unresolved and resolved sources of gravitational waves are at the origin of a stochastic gravitational wave background. While the computation of its mean density as a function of frequency in a homogeneous and isotropic universe is standard…

Cosmology and Nongalactic Astrophysics · Physics 2018-07-19 Giulia Cusin , Cyril Pitrou , Jean-Philippe Uzan

Using the surface photometric analysis data for a well defined sample of 79 nearby radio galaxies (z < 0.12), it is shown that the level of radio emission associated with an elliptical galaxy during the radio-loud phase is related to the…

Astrophysics · Physics 2009-11-10 Gopal-Krishna , Amit R. Dhakulkar , Paul J. Wiita , Samir Dhurde

Polarized foregrounds are going to be a serious challenge for detecting CMB cosmological B-modes. Both diffuse Galactic emission and extragalactic sources contribute significantly to the power spectrum on large angular scales. At low…

Cosmology and Nongalactic Astrophysics · Physics 2010-05-17 Clive Dickinson

Synchrotron diffuse radiation (SDR) emission is one of the major Galactic components, in the 100 MHz up to 100 GHz frequency range. Its spectrum and sky map provide valuable measure of the galactic cosmic ray electrons (GCRE) in the…

High Energy Astrophysical Phenomena · Physics 2018-11-08 Giuseppe Di Bernardo , Dario Grasso , Carmelo Evoli , Daniele Gaggero

New measurements of galaxy clustering and background radiations provide improved constraints on the isotropy and homogeneity of the Universe on large scales. In particular, the angular distribution of radio sources and the X-Ray Background…

Astrophysics · Physics 2009-10-16 Kelvin K. S. Wu , Ofer Lahav , Martin J. Rees

In principle, the angular anisotropy in the extragalactic gamma-ray background (EGRB) places severe constraints upon putative populations of unresolved gamma-ray point sources. Existing estimates of the EGRB anisotropy have been constructed…

Cosmology and Nongalactic Astrophysics · Physics 2018-03-02 Avery E. Broderick , Christoph Pfrommer , Ewald Puchwein , Philip Chang , Kendrick M. Smith

A sample of 129 unresolved radio sources with ultrahigh linear polarization (>30 per cent) has been selected from the NRAO VLA Sky Survey. Such high average linear polarization is unusual in extragalactic sources. Higher resolution…

Astrophysics of Galaxies · Physics 2010-09-21 H. Shi , H. Liang , J. L. Han , R. W. Hunstead

We present a search for the synchrotron emission from the synchrotron cosmic web by cross correlating 180MHz radio images from the Murchison Widefield Array with tracers of large scale structure (LSS). We use two versions of the radio image…

Cosmology and Nongalactic Astrophysics · Physics 2017-04-12 Tessa Vernstrom , Bryan M. Gaensler , Shea Brown , Emil Lenc , Ray P. Norris

The universe is filled with a diffuse and isotropic extragalactic background of gamma-ray radiation, containing roughly equal energy flux per decade in photon energy between 3 MeV-100 GeV. The origin of this background is one of the…

Astrophysics · Physics 2011-05-05 Abraham Loeb , Eli Waxman

Synchrotron radiation from the interstellar medium (ISM) of our galaxy dominates the sky brightness at low radio frequencies, and carries information about relativistic and thermal electron distributions across a range of astrophysical…

Astrophysics of Galaxies · Physics 2019-03-18 Colin Lonsdale , Elena Orlando , Gregg Hallinan , Greg Taylor , Clive Dickinson