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Related papers: The isotropic radio background revisited

200 papers

Contribution of resolved and unresolved extragalactic point sources to the low-frequency sky spectrum is a potentially non-negligible part of the astrophysical foregrounds for cosmic dawn 21-cm experiments. The clustering of such point…

Cosmology and Nongalactic Astrophysics · Physics 2024-10-01 Shikhar Mittal , Girish Kulkarni , Dominic Anstey , Eloy de Lera Acedo

We summarize the radio synchrotron background workshop that took place July 19-21, 2017 at the University of Richmond. This first scientific meeting dedicated to the topic was convened because current measurements of the diffuse radio…

We obtain the dipolar anisotropies in the arrival directions of ultra-high energy cosmic rays diffusing from nearby extragalactic sources. We discuss both the energy regime of spatial diffusion and the quasi-rectilinear one leading to just…

High Energy Astrophysical Phenomena · Physics 2014-06-11 Diego Harari , Silvia Mollerach , Esteban Roulet

This is the third in a series of papers that present observations and results for a sample of 76 ultra-steep-spectrum radio sources designed to find galaxies at high redshift. Here we present multi-frequency radio observations, from the…

Astrophysics · Physics 2009-11-11 I. J. Klamer , R. D. Ekers , J. J. Bryant , R. W. Hunstead , E. M. Sadler , C. De Breuck

[Abridged] We present updated estimates of Galactic foreground emission using seven years of WMAP data. Using the power spectrum of differences between multi-frequency template-cleaned maps, we find no evidence for foreground contamination…

The Australia Telescope 20 GHz (AT20G) survey is a blind survey of the whole Southern sky at 20 GHz with follow-up observations at 4.8, 8.6, and 20 GHz carried out with the Australia Telescope Compact Array (ATCA). In this paper we present…

The all-sky 408 MHz map of Haslam et al. is one the most important total-power radio surveys. It has been widely used to study diffuse synchrotron radiation from our Galaxy and as a template to remove foregrounds in cosmic microwave…

Instrumentation and Methods for Astrophysics · Physics 2015-06-11 M. Remazeilles , C. Dickinson , A. J. Banday , M. -A. Bigot-Sazy , T. Ghosh

Context. The diffuse X-ray emission surrounding radio galaxies is generally interpreted either as due to inverse Compton scattering of non-thermal radio-emitting electrons on the Cosmic Microwave Background (IC/CMB), or as the thermal…

Astrophysics of Galaxies · Physics 2021-03-17 A. Paggi , F. Massaro , H. A. Pena-Herazo , V. Missaglia , F. Ricci , C. Stuardi , R. P. Kraft , G. R. Tremblay , S. A. Baum , B. J. Wilkes

We present a new assessment of the contribution of Blazars to the extragalactic background radiation across the e.m. spectrum. Our calculations rely on deep Blazar radio counts that we derived combining several multifrequency surveys. The…

Astrophysics · Physics 2009-11-13 P. Giommi , S. Colafrancesco , E. Cavazzuti , M. Perri , C. Pittori

Large-scale cosmic microwave background anisotropies in homogeneous, globally anisotropic cosmologies are investigated. We perform a statistical analysis in which the four-year data from the Cosmic Background Explorer satellite is searched…

Astrophysics · Physics 2008-11-26 Emory. F. Bunn , Pedro Ferreira , Joseph Silk

Astrophysical sources outside the Milky Way, such as active galactic nuclei and star-forming galaxies, leave their imprint on the gamma-ray sky as nearly isotropic emission referred to as the Extragalactic Gamma-Ray Background (EGB). While…

High Energy Astrophysical Phenomena · Physics 2017-01-12 Mariangela Lisanti , Siddharth Mishra-Sharma , Lina Necib , Benjamin R. Safdi

We review the current understanding of the diffuse gamma-ray background (DGRB). The DGRB is what remains of the total measured gamma-ray emission after the subtraction of the resolved sources and of the diffuse Galactic foregrounds. It is…

Cosmology and Nongalactic Astrophysics · Physics 2015-09-28 Mattia Fornasa , Miguel A. Sanchez-Conde

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

We introduce new symmetry-based methods to test for isotropy in cosmic microwave background radiation. Each angular multipole is factored into unique products of power eigenvectors, related multipoles and singular values that provide 2 new…

Astrophysics · Physics 2008-11-26 Pramoda Kumar Samal , Rajib Saha , Pankaj Jain , John P. Ralston

We have used the upgraded Giant Metrewave Radio Telescope to map the Coma cluster of galaxies at 250-500 MHz and 1050-1450 MHz bands. These 6.26 arcsec and 2.18 arcsec resolutions observations allow detailed radio structures to be…

Astrophysics of Galaxies · Physics 2021-06-01 Dharam V. Lal

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

(Abridged) While the major contribution to the Cosmic Microwave Background (CMB) anisotropies are the sought-after primordial fluctuations produced at the surface of last scattering, other effects produce secondary fluctuations at lower…

Astrophysics · Physics 2009-10-30 A. Refregier , D. N. Spergel , T. Herbig

We constrain Galactic foreground contamination of the Python V cosmic microwave background anisotropy data by cross correlating it with foreground contaminant emission templates. To model foreground emission we use 100 and 12 $\mu$m dust…

Astrophysics · Physics 2009-11-07 Pia Mukherjee , Kim Coble , Mark Dragovan , Ken Ganga , John Kovac , Bharat Ratra , Tarun Souradeep

We follow up on a report by Vacca et al. (2018) of 28 candidate large-scale diffuse synchrotron sources in an 8{\deg}$\times$8{\deg} area of the sky (centred at RA 5h0m0s Dec 5{\deg}48'0''). These sources were originally observed at 1.4 GHz…

Astrophysics of Galaxies · Physics 2022-05-27 Torrance Hodgson , Melanie Johnston-Hollitt , Benajmin McKinley , Tessa Vernstrom , Valentina Vacca

We present a combined radio/X-ray study of six massive galaxy clusters, aimed at determining the potential for heating of the intra-cluster medium (ICM) by non-central radio galaxies. Since X-ray cavities associated with the radio lobes of…

Cosmology and Nongalactic Astrophysics · Physics 2022-04-27 Ruchika Seth , Ewan O'Sullivan , Biny Sebastian , Somak Raychaudhury , Gerrit Schellenberger , Christopher P. Haines