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Related papers: The isotropic radio background revisited

200 papers

Radio galaxies are promising candidates as the sources of ultrahigh energy cosmic rays (UHECRs). In this work, we examine if the stringent constraints imposed by the dipole and quadropole anisotropies as well as the UHECR spectrum and…

High Energy Astrophysical Phenomena · Physics 2022-07-06 Björn Eichmann , Michael Kachelrieß , Foteini Oikonomou

Spectral measurements of the 21 cm monopole background have the promise of revealing the bulk energetic properties and ionization state of our universe from z ~ 6-30. Synchrotron foregrounds are orders of magnitude larger than the…

Cosmology and Nongalactic Astrophysics · Physics 2014-10-08 Eric R. Switzer , Adrian Liu

Galactic synchrotron emission represents the most relevant foreground contamination in cosmic microwave background (CMB) anisotropy observations at angular scales $\theta \gsim 1^\circ$ and frequencies $\nu \lsim 70$ GHz. The accurate…

I investigate the effect of non-uniform magnetic fields in the extended structures of radio galaxies on the observed synchrotron and inverse-Compton emission. On the assumption of an isotropic field, with a given power spectrum and a…

High Energy Astrophysical Phenomena · Physics 2015-06-16 M. J. Hardcastle

We calculate intensity and angular power spectrum of the cosmological background of synchrotron emission from cold dark matter annihilations into electron positron pairs. We compare this background with intensity and anisotropy of…

Astrophysics · Physics 2011-07-13 Le Zhang , Guenter Sigl

We use the GALPROP model for cosmic-ray (CR) propagation to obtain our best prediction of the Galactic component of gamma rays, and show that away from the Galactic plane it gives an accurate prediction of the observed EGRET intensities. On…

Astrophysics · Physics 2007-05-23 A. W. Strong , I. V. Moskalenko , O. Reimer

The Galactic disc is opaque to radio waves from extragalactic sources with frequencies nu less than ~3 MHz. However, radio waves with kHz, Hz, and even lower frequencies may propagate through the intergalactic medium (IGM). I argue that the…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 Brian C. Lacki

Understanding diffuse Galactic radio emission is interesting both in its own right and for minimizing foreground contamination of cosmological measurements. Cosmic Microwave Background experiments have focused on frequencies > 10 GHz,…

We examine the brightness of the Cosmic Radio Background (CRB) by comparing the contribution from individual source counts to absolute measurements. We use a compilation of radio counts to estimate the contribution of detected sources to…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 Tessa Vernstrom , Douglas Scott , Jasper Wall

The analysis of the recent WMAP source catalog shows that the vast majority of bright foreground extragalactic sources detected in CMB maps are Blazars. In this paper we calculate the contamination of CMB anisotropy maps by this type of…

Astrophysics · Physics 2009-11-07 P. Giommi , S. Colafrancesco

We review estimates of small scale fluctuations due to extragalactic point sources in the Planck Surveyor frequency bands. While our undestanding of the spectral and evolutionary properties of these sources is far from complete,…

Astrophysics · Physics 2007-05-23 G. De Zotti , L. Toffolatti , G. L. Granato

Recently the EDGES experiment has claimed the detection of an absorption feature centered at 78 MHz. When interpreted as a signature of cosmic dawn, this feature appears at the correct wavelength (corresponding to a redshift range of…

High Energy Astrophysical Phenomena · Physics 2018-08-15 Prateek Sharma

The inverse Compton scattering of interstellar photons off cosmic-ray electrons seems to play a more important role in the generation of diffuse emission from the Galaxy than thought before. The background radiation field of the Galaxy is…

Astrophysics · Physics 2009-10-31 I. V. Moskalenko , A. W. Strong

The bright polarized synchrotron emission, away from the Galactic plane, originates mostly from filamentary structures. We implement a filament finder algorithm which allows the detection of bright elongated structures in polarized…

Cosmology and Nongalactic Astrophysics · Physics 2023-04-26 F. A. Martire , A. J. Banday , E. Martínez-González , R. B. Barreiro

With the Westerbork Synthesis Radio Telescope (WSRT), multi-frequency polarimetric images were taken of the diffuse radio synchrotron background in a region centered on (l,b) = (161,16). The observations were done simultaneously in 5…

Astrophysics · Physics 2011-05-23 Marijke Haverkorn , Peter Katgert , Ger de Bruyn

The Galactic foreground contamination in CMBR anisotropies, especially from the dust component, is not easily separable from the cosmological or extragalactic component. In this paper, some doubts will be raised concerning the validity of…

Astrophysics · Physics 2009-11-13 M. Lopez-Corredoira

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

The contribution of the Unresolved Extragalactic Radio Sources to the diffuse brightness of the sky was evaluated using the source number - flux measurements available in literature. We first optimized the fitting function of the data based…

Astrophysics · Physics 2009-11-13 M. Gervasi , A. Tartari , M. Zannoni , G. Boella , G. Sironi

As a pilot study for the first all-sky radio survey at short wavelengths, we have observed 1216 sq. deg. of the southern sky at 18GHz (16mm) using a novel wide-band (3.4GHz bandwidth) analogue correlator on one baseline of the Australia…

Our position inside the Galaxy requires all-sky surveys to reveal its large-scale properties. The zero-level calibration of all-sky surveys differs from standard 'relative' measurements, where a source is measured in respect to its…

Astrophysics · Physics 2009-11-13 Wolfgang Reich , Patricia Reich