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Observers have demonstrated that it is now feasible to measure the cosmic microwave background (CMB) temperature at high redshifts. We explore the possible constraints on cosmology which might ultimately be derived from such measurements.…

Astrophysics · Physics 2009-11-07 John M. LoSecco , Grant J. Mathews , Yun Wang

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.…

Astrophysics · Physics 2009-10-28 Douglas Scott , Joe Silk , Martin White

In a concordant $\Lambda$ Cold Dark Matter ($\Lambda$CDM) model, large-angle Cosmic Microwave Background (CMB) temperature anisotropy due to linear perturbations in the local universe is not negligible. We explore a possible role of an…

Cosmology and Nongalactic Astrophysics · Physics 2012-04-09 Kaiki Taro Inoue

The excess of cosmic-ray positrons in the energy range from 10 GeV to few hundred GeV reported by PAMELA and AMS experiments is not consistent with a pure secondary origin and requires the introduction of a source term. The presence of…

Instrumentation and Methods for Astrophysics · Physics 2015-10-07 J. Berdugo , J. Casaus , C. Mana , M. A. Velasco

We use the Wilkinson Microwave Anisotropy Probe 7-year data (WMAP7) to further probe point source detection technique in the sky maps of the cosmic microwave background (CMB) radiation. The method by Tegmark et al. for foreground reduced…

Cosmology and Nongalactic Astrophysics · Physics 2013-07-30 H. G. Khachatryan , G. Nurbaeva , D. Pfenniger , G. Meylan

Measurements of cosmic microwave background (CMB) anisotropies constrain isocurvature fluctuations between photons and non-relativistic particles to be sub-dominant to adiabatic fluctuations. Perturbations in the relative number densities…

Cosmology and Nongalactic Astrophysics · Physics 2012-01-09 Daniel Grin , Olivier Doré , Marc Kamionkowski

Full sky maps are made in five microwave frequency bands to separate the temperature anisotropy of the CMB from foreground emission. We define masks that excise regions of high foreground emission. The effectiveness of template fits to…

Our motion through the Universe generates a dipole in the temperature anisotropies of the Cosmic Microwave Background (CMB) and also in the angular distribution of sources. If the cosmological principle is valid, these two dipoles are…

Cosmology and Nongalactic Astrophysics · Physics 2023-06-09 Charles Dalang , Camille Bonvin

The contribution of unresolved sources to the diffuse gamma-ray background could produce anisotropies in this emission on small angular scales. Recent studies have considered the angular power spectrum and other anisotropy metrics as tools…

High Energy Astrophysical Phenomena · Physics 2019-08-14 Jennifer M. Siegal-Gaskins

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…

Cosmology and Nongalactic Astrophysics · Physics 2022-04-06 Raghunath Ghara , Garrelt Mellema , Saleem Zaroubi

We present measurements of a population of matched radio sources at 1.4 and 5 GHz down to a flux limit of 1.5 mJy in 7 sq. degs. of the NOAO Deep Field South. We find a significant fraction of sources with inverted spectral indices that all…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 Michael D. Schneider , Robert H. Becker , Willem de Vries , Richard L. White

We constrain several models of the early Universe that predict a statistical anisotropy of the cosmic microwave background (CMB) sky. We make use of WMAP9 maps deconvolved with beam asymmetries. As compared to previous releases of WMAP…

Cosmology and Nongalactic Astrophysics · Physics 2014-03-03 Sabir Ramazanov , Grigory Rubtsov

(Abridged) Recent cosmic microwave background anisotropy results from the Wilkinson Microwave Anisotropy Probe suggest that the universe was reionized at a redshift around 20. Such an early reionization could arise through the ionizing…

Astrophysics · Physics 2008-11-26 Asantha Cooray , James J. Bock , Brian Keating , Andrew E. Lange , T. Matsumoto

It is well-known that first order phase transitions in the early universe can be a powerful source of observable stochastic gravitational wave backgrounds. Any such gravitational wave background must exhibit large-scale anisotropies at…

High Energy Physics - Phenomenology · Physics 2023-06-21 Arushi Bodas , Raman Sundrum

The observed features of the radio sources indicate complex propagation effects embedded in the waves of solar radio bursts. In this work, we perform ray-tracing simulations on radio wave transport in the corona and interplanetary region…

Solar and Stellar Astrophysics · Physics 2021-03-24 PeiJin Zhang , ChuanBing Wang , Eduard P. Kontar

The natural outcome of theoretical calculations of microwave background anisotropy is the angular power spectrum ${\cal C}_\ell$ as a function of multipole number $\ell$. Experimental ${\cal C}_\ell$'s are needed for direct comparison.…

Astrophysics · Physics 2009-09-25 J. Richard Bond

We present millimeter wavelength detections of three faint sources that are most likely high-redshift starburst galaxies. For one of the sources, which was previously discovered with SCUBA at 850 mu m, we present a detection with the IRAM…

Thomson scattering of the Cosmic Microwave Background (CMB) on moving electrons in the outflows of Lyman Break Galaxies (LBGs) at redshifts 2-8 contributes to the small-scale CMB anisotropies. The net effect produced by each outflow depends…

Astrophysics · Physics 2009-11-11 Daniel Babich , Abraham Loeb

We present the results of a Cosmic Microwave Background (CMB) anisotropy ground-based millimetric experiment sensitive to fluctuations on angular scales of $\sim 2\degg$. Four independent bands centered at 3.3, 2.1, 1.3 and 1.1 mm collected…

Astrophysics · Physics 2009-10-30 B. Femenia , R. Rebolo , C. M. Gutierrez , M. Limon , L. Piccirillo
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