相关论文: Cosmological observations in the radio domain: the…
With the TRIS experiment we have performed absolute measurements of the sky brightness in a sky circle at $\delta = +42^{\circ}$ at the frequencies $\nu =$ 0.60, 0.82 and 2.5 GHz. In this paper we discuss the techniques used to separate the…
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…
We estimate the contribution of extragalactic radio sources to fluctuations in sky temperature over the range of frequencies (10-300 GHz) used for Cosmic Microwave Background (CMB) anisotropy measurements. CMB anisotropy observations at…
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…
At frequencies close to 1 GHz the sky diffuse radiation is a superposition of radiation of Galactic origin, the 3 K Relic or Cosmic Microwave Background Radiation, and the signal produced by unresolved extragalactic sources. Because of…
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…
We use absolutely calibrated data between 3 and 90 GHz from the 2006 balloon flight of the ARCADE 2 instrument, along with previous measurements at other frequencies, to constrain models of extragalactic emission. Such emission is a…
Confusion noise due to extragalactic sources is a fundamental astrophysical limitation for experiments aimed at accurately determining the power spectrum of the Cosmic Microwave Background (CMB) down to arcmin angular scales and with a…
The ARCADE 2 instrument has measured the absolute temperature of the sky at frequencies 3, 8, 10, 30, and 90 GHz, using an open-aperture cryogenic instrument observing at balloon altitudes with no emissive windows between the beam-forming…
We report the results of an effort to measure the low frequency portion of the spectrum of the Cosmic Microwave Background Radiation (CMB), using a balloon-borne instrument called ARCADE (Absolute Radiometer for Cosmology, Astrophysics, and…
We estimate the level of confusion to Cosmic Microwave Background anisotropy measurements caused by extragalactic infrared sources. CMB anisotropy observations at high resolution and high frequencies are especially sensitive to this…
Since the measurements of COBE/FIRAS in the mid-90's we know that the energy spectrum of the cosmic microwave background (CMB) is extremely close to that of a perfect blackbody at an average temperature T0~2.726K. However, a number of…
Spectral distortions of the Cosmic Microwave Background (CMB) offer the possibility of probing processes which occurred during the evolution of our Universe going back up to Z$\simeq 10^7$. Unfortunately all the attempts so far carried out…
We have observed the cosmic microwave background temperature fluctuations in eight fields covering three separated areas of sky with the Very Small Array at 34 GHz. A total area of 101 square degrees has been imaged, with sensitivity on…
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…
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…
One of the explanations for the recent EDGES-LOW band 21-cm measurements of a strong absorption signal around 80~MHz is the presence of an excess radio background to the Cosmic Microwave Background (CMB). Such excess can be produced by the…
Recently the ARCADE 2 experiment measured the cosmic radio background (CRB) and found the brightness temperature of the CRB at 1.4 GHz to be ~480 mK. Integrating the flux density from the observed 1.4 GHz radio source count produces a…
This work presents a detailed analysis of Cosmic Microwave Background (CMB) radiation intensity observations. The CMB is a relic of the Big Bang and its study greatly enhances our knowledge of cosmology. This work has led to new values for…
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,…