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Related papers: Three-Point Correlations in the COBE-DMR Two-Year …

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The sky-RMS is the simplest model-independent characterization of a cosmological anisotropy signal. The RMS temperature fluctuations determined from the $COBE$-DMR four-year sky maps are frequency independent, consistent with the hypothesis…

We investigate the angular two-point correlation function of temperature in the WMAP maps. Updating and extending earlier results, we confirm the lack of correlations outside the Galaxy on angular scales greater than about 60 degrees at a…

Astrophysics · Physics 2013-08-27 Craig J. Copi , Dragan Huterer , Dominik J. Schwarz , Glenn D. Starkman

We present a study of the 3-pt angular correlation function w_3= <delta_1 delta_2 delta_3> of (adimensional) temperature anisotropies measured by the Wilkinson Microwave Anisotropy Probe (WMAP). Results can be normalized to the 2-point…

Astrophysics · Physics 2009-11-07 E. Gaztanaga , J. Wagg

On large angular scales (greater than about 60 degrees), the two-point angular correlation function of the temperature of the cosmic microwave background (CMB), as measured (outside of the plane of the Galaxy) by the Wilkinson Microwave…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 Devdeep Sarkar , Dragan Huterer , Craig J. Copi , Glenn D. Starkman , Dominik J. Schwarz

We compute the contribution to the three--point temperature correlation function of the Cosmic Microwave Background coming from the non--linear evolution of Gaussian initial perturbations, as described by the Rees--Sciama (or integrated…

Astrophysics · Physics 2011-05-10 Silvia Mollerach , Alejandro Gangui , Francesco Lucchin , Sabino Matarrese

Full-sky maps of the cosmic microwave background temperature reveal a 7% asymmetry of fluctuation power between two halves of the sky. A common phenomenological model for this asymmetry is an overall dipole modulation of statistically…

Cosmology and Nongalactic Astrophysics · Physics 2015-10-07 Simone Aiola , Bingjie Wang , Arthur Kosowsky , Tina Kahniashvili , Hassan Firouzjahi

We extend a previous bispectrum analysis of the COBE-DMR 4 year maps, allowing for the presence of correlations between all possible angular scales. We find that the non-Gaussian signal found earlier for bispectrum components including…

Astrophysics · Physics 2009-10-31 H. B. Sandvik , J. Magueijo

We present the two- and three-point real space correlation functions of the five-year WMAP sky maps, and compare the observed functions to simulated LCDM concordance model ensembles. In agreement with previously published results, we find…

Cosmology and Nongalactic Astrophysics · Physics 2010-01-23 E. Gjerløw , H. K. Eriksen , A. J. Banday , K. M. Górski , P. B. Lilje

After the detection of structure in the microwave sky, the characterization of the observed features may be a useful guide to current and future experiments. The first year COBE-DMR sky maps were analyzed in order to identify the most…

Astrophysics · Physics 2007-05-23 S. Torres

Two-point correlation functions are ubiquitous tools of modern cosmology, appearing in disparate topics ranging from cosmological inflation to late-time astrophysics. When the background spacetime is maximally symmetric, invariance…

General Relativity and Quantum Cosmology · Physics 2017-02-22 Oton H. Marcori , Thiago S. Pereira

We perform a discrete wavelet analysis of the COBE-DMR 4yr sky maps and find a significant scale-scale correlation on angular scales from about 11 to 22 degrees, only in the DMR face centered on the North Galactic Pole. This non-Gaussian…

Astrophysics · Physics 2009-10-31 Jesus Pando , David Valls-Gabaud , Li-Zhi Fang

We present theoretical and observational studies of non-Gaussian fluctuations in CMB, by using the angular bispectrum and trispectrum. We predict the primary angular bispectrum from inflation, and forecast how well we can measure the…

Astrophysics · Physics 2007-05-23 Eiichiro Komatsu

We present new full-sky temperature maps in five frequency bands from 23 to 94 GHz, based on the first three years of the WMAP sky survey. The new maps, which are consistent with the first-year maps and more sensitive, incorporate…

We have searched the temperature maps from the COBE Differential Microwave Radiometers (DMR) first two years of data for evidence of unresolved sources. The high-latitude sky (|b| > 30\deg) contains no sources brighter than 192 uK…

We investigate the statistical anisotropy and Gaussianity of temperature fluctuations of Cosmic Microwave Background radiation (CMB) data from {\it Wilkinson Microwave Anisotropy Probe} survey, using the multifractal detrended fluctuation…

Astrophysics · Physics 2011-08-04 M. Sadegh Movahed , F. Ghasemi , Sohrab Rahvar , M. Reza Rahimi Tabar

We analyze the Cosmic Microwave Background (CMB) anisotropy data from the independent COBE FIRAS and DMR observations. We extract the frequency spectrum of the FIRAS signal that has the spatial distribution seen by DMR and show that it is…

Astrophysics · Physics 2009-10-30 D. J. Fixsen , G. Hinshaw , C. L. Bennett , J. C. Mather

We present limits to the amplitude of non-Gaussian primordial fluctuations in the WMAP 1-year cosmic microwave background sky maps. A non-linear coupling parameter, f_NL, characterizes the amplitude of a quadratic term in the primordial…

The frequency-independent RMS temperature fluctuations determined from the COBE-DMR two year sky maps are used to infer the parameter Q_{rms-PS}, which characterizes the normalization of power law models of primordial cosmological…

We consider several factors concerning the design of observing strategies in Cosmic Microwave Background (CMB) anisotropy experiments. First we consider the number of independent points on the sky one should observe given a fixed observing…

Astrophysics · Physics 2007-05-23 R. K. Schaefer , L. Piccirillo

We study statistical anisotropies generated in the observed two-point function of the cosmic microwave background (CMB) fluctuations if the primordial statistics are non-Gaussian. Focusing on the dipole modulations of the anisotropies, we…

Cosmology and Nongalactic Astrophysics · Physics 2018-07-17 Saroj Adhikari , Anne-Sylvie Deutsch , Sarah Shandera