相关论文: The unusual smoothness of the extragalactic unreso…

Analyses of measurements of the distribution of absolute brightness temperature over the radio sky have led recently to suggestions that there exists a substantial unexplained extragalactic radio background. Consequently, there have been…

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…

Observations of the extragalactic radio background have uncovered a significant isotropic emission across multiple frequencies spanning from 22 MHz to 10 GHz. The intensity of this non-thermal emission component significantly exceeds the…

The ARCADE 2 collaboration has reported a significant excess in the isotropic radio background, whose homogeneity cannot be reconciled with clustered sources. This suggests a cosmological origin prior to structure formation. We investigate…

We report on the detection of a feature with negative radio flux in a sensitive, low resolution observation with the VLA. This morphologically peculiar feature is approximately 25" 65" in size with a peak central amplitude of about -0.25 mK…

The efficiency of radio emission is an important unknown parameter of early galaxies at cosmic dawn, as models with high efficiency have been shown to modify the cosmological 21-cm signal substantially, deepening the absorption trough and…

Recent measurements by the ARCADE2 experiment unambiguously show an excess in the isotropic radio background at frequencies below the GHz scale. We argue that this excess may be a natural consequence of the interaction of visible and dark…

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…

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…

We present a short overview on the extragalactic background radiation from radio to X-rays, with an eye to the relation to galaxy formation and emphasizing on astrophysical backgrounds (as opposed to cosmological). As the radio background,…

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…

Radio observations at multiple frequencies have detected a significant isotropic emission component between 22~MHz and 10~GHz, commonly termed the ARCADE-2 Excess. The origin of this radio emission is unknown, as the intensity, spectrum and…

The low frequency tail of the CMB spectrum, down along the radio range (~1 GHz), may carry weak spectral distortions which are fingerprints of processes occurred during different epochs of the thermal history of the Universe, from z~3\times…

We investigate different scenarios for the origin of the extragalactic radio background. The surface brightness of the background, as reported by the ARCADE 2 collaboration, is several times higher than that which would result from…

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…

We explore the possibility of detecting the excess of the cosmic radio background (CRB) toward galaxy clusters due to its Compton scattering by electrons of the hot intergalactic gas. When mapping the background fluctuations at frequencies…

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…

Fluctuations in the temperature of the cosmic microwave background have now been detected over a wide range of angular scales, and a consistent picture seems to be emerging. This article describes some of the implications for cosmology.…

New calculations of the Galactic contamination over microwave background radiation anisotropies are carried out. On one hand, when a frequency-dependent contrast of molecular clouds with respect to the Galactic background of the diffuse…

The sky distribution of cosmic rays with energies above the 'GZK cutoff' holds important clues to their origin. The AGASA data, although consistent with isotropy, shows evidence for small-angle clustering, and it has been argued that such…