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A fundamental assumption in cosmology is that of statistical isotropy - that the universe, on average, looks the same in every direction in the sky. Statistical isotropy has recently been tested stringently using Cosmic Microwave Background…

Cosmology and Nongalactic Astrophysics · Physics 2011-09-14 Caroline Zunckel , Dragan Huterer , Glenn D. Starkman

The polarization of the Cosmic Microwave Background (CMB)is a powerful observational tool at hand for modern cosmology. It allows to break the degeneracy of fundamental cosmological parameters one cannot obtain using only anisotropy data…

Astrophysics · Physics 2009-11-07 M. V. Sazhin , G. Sironi , O. S. Khovanskaya

Measurements of the cosmic microwave background (CMB) radiation provide a unique opportunity for a direct study of the primordial cosmic plasma at redshift z ~1000. The angular power spectra of temperature and polarisation fluctuations are…

Astrophysics · Physics 2009-11-10 Marco Bersanelli , Davide Maino , Aniello Mennella

It is discovered in our previous work that different observational systematics, e.g., errors of antenna pointing directions, asynchronous between the attitude and science data, can generate pseudo-dipole signal in full-sky maps of the…

Cosmology and Nongalactic Astrophysics · Physics 2011-01-19 Hao Liu , Ti-Pei Li

Recent observations opened up a new window on the inflationary model building. As it was firstly reported by the WMAP data, there may be some indications of statistical anisotropy on the CMB map, although the statistical significance of…

Cosmology and Nongalactic Astrophysics · Physics 2015-11-06 Razieh Emami

We use wavelet and curvelet transforms to extract signals of cosmic strings from cosmic microwave background (CMB) temperature anisotropy maps, and to study the limits on the cosmic string tension which various ongoing CMB temperature…

Cosmology and Nongalactic Astrophysics · Physics 2017-06-21 Lukas Hergt , Adam Amara , Robert Brandenberger , Tomasz Kacprzak , Alexandre Refregier

In cosmic microwave background (CMB) experiments, foreground-cleaned temperature maps are still contaminated by the residual dipole due to uncertainties of the Doppler dipole direction and microwave radiometer sidelobe. To obtain reliable…

Cosmology and Nongalactic Astrophysics · Physics 2013-01-16 Hao Liu , Ti-Pei Li

We propose a new method for extracting the non-Gaussian signatures on the isotemperature statistics in the cosmic microwave background (CMB) sky, which is induced by the gravitational lensing due to the intervening large-scale structure of…

Astrophysics · Physics 2009-11-06 Masahiro Takada

The Cosmic Microwave Background (CMB) anisotropies measurements can provide many clues about the Universe. Although the common belief is that they will allow a very precise measurement of the cosmological parameters (that is, the current…

Astrophysics · Physics 2007-05-23 Alain Riazuelo , David Langlois

The Cosmic Microwave Background (CMB) anisotropy power on the largest angular scales observed both by WMAP and COBE DMR appears to be lower than the one predicted by the standard model of cosmology with almost scale free primordial…

Astrophysics · Physics 2009-09-29 Carlo R. Contaldi , Marco Peloso , Lev Kofman , Andrei Linde

An unexpected distribution of temperatures in the CMB could be a sign of new physics. In particular, the existence of cosmic defects could be indicated by temperature discontinuities via the Kaiser-Stebbins effect. In this paper, we show…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-17 Jude Bowyer , Andrew H. Jaffe

We present a new method for calculating linear cosmic microwave background (CMB) anisotropy spectra based on integration over sources along the photon past light cone. In this approach the temperature anisotropy is written as a time…

Astrophysics · Physics 2008-11-26 Uros Seljak , Matias Zaldarriaga

The Standard Inflationary model predicts an isotropic distribution of the Cosmic Microwave Background temperature fluctuations. Detection of deviations from statistical isotropy would call for a revision of the physics of the early…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 Laura Cayon

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

The peculiar motion of the Earth causes a dipole anisotropy modulation in the distant galaxy distribution due to the aberration effect. However, the amplitude and angular direction of the effect is not necessarily the same as those of the…

Cosmology and Nongalactic Astrophysics · Physics 2010-10-12 Yousuke Itoh , Kazuhiro Yahata , Masahiro Takada

We introduce and study the distribution of an estimator for the normalized bispectrum of the Cosmic Microwave Background (CMB) anisotropy. We use it to construct a goodness of fit statistic to test the coadded 53 and 90 GHz COBE-DMR 4 year…

Astrophysics · Physics 2009-10-30 Pedro G. Ferreira , Joao Magueijo , Krzysztof M. Górski

Several unexpected features have been observed in the microwave sky at large angular scales, both by WMAP an by Planck. Among those features is a lack of both variance and correlation on the largest angular scales, alignment of the lowest…

Cosmology and Nongalactic Astrophysics · Physics 2016-09-07 Dominik J. Schwarz , Craig J. Copi , Dragan Huterer , Glenn D. Starkman

Under the assumption that the concordance Lambda-cold dark matter (CDM) model is the correct model, we test the cosmic microwave background (CMB) anisotropy data for systematic effects by examining the band pass temperature residuals with…

Astrophysics · Physics 2009-11-10 Louise M. Griffiths , Charles H. Lineweaver

We apply the Gabor transform methodology proposed in (Hansen et al. 2002, 2003) to the WMAP data in order to test the statistical properties of the CMB fluctuation field and specifically to evaluate the fundamental assumption of…

Astrophysics · Physics 2009-05-29 F. K. Hansen , A. J. Banday , K. M. Gorski

We apply spherical needlets to the Wilkinson Microwave Anisotropy Probe 5-year cosmic microwave background (CMB) dataset, to search for imprints of non-isotropic features in the CMB sky. We use the needlets localization properties to…

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