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Related papers: Peculiarities of phases of the WMAP quadrupole

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We present a circular cross-correlation tests for the phases of the Internal Linear Combination Map (ILC) and {\it WMAP}'s foregrounds for all K--W frequency bands at the range of multipoles $\ell\le 50$. We have found significant…

Astrophysics · Physics 2009-11-10 P. D. Naselsky , A. G. Doroshkevich , O. V. Verkhodanov

We present circular and linear cross-correlation tests and the "friend-of-friend" analysis for phases of the Internal Linear Combination Map (ILC) and the WMAP foregrounds for all K--W frequency bands at the range of multipoles…

Astrophysics · Physics 2009-11-10 P. D. Naselsky , A. G. Doroshkevich , O. V. Verkhodanov

[Abridged] We have produced a cleaned map of the Wilkinson Microwave Anisotropy Probe (WMAP) 3-year data using an improved foreground subtraction technique. We perform an internal linear combination (ILC) to subtract the Galactic foreground…

Astrophysics · Physics 2008-11-26 Chan-Gyung Park , Changbom Park , J. Richard Gott

We discuss the problem of the bias of the Internal Linear Combination (ILC) CMB map and show that it is closely related to the coefficient of cross-correlation K(l) of the true CMB and the foreground for each multipole l. We present…

Astrophysics · Physics 2009-06-23 Pavel D. Naselsky , Oleg V. Verkhodanov , Mikkel T. B. Nielsen

The issue of non-Gaussianity is not only related to distinguishing the theories of the origin of primordial fluctuations, but also crucial for the determination of cosmological parameters in the framework of inflation paradigm. We present…

Astrophysics · Physics 2009-11-10 Lung-Yih Chiang , Pavel D. Naselsky

We study the Internal Linear Combination (ILC) method presented by the Wilkinson Microwave Anisotropy Probe (WMAP) science team, with the goal of determining whether it may be used for cosmological purposes, as a template-free alternative…

Astrophysics · Physics 2009-07-09 H. K. Eriksen , A. J. Banday , K. M. Gorski , P. B. Lilje

Following this astro-ph communication, we release a set of 10,000 WMAP ILC simulations, produced as described by Eriksen et al. (2004). We strongly encourage that an analysis of these simulations accompanies any scientific analysis of the…

Astrophysics · Physics 2007-05-23 H. K. Eriksen , A. J. Banday , K. M. Gorski , P. B. Lilje

The large-angle (low-ell) correlations of the Cosmic Microwave Background (CMB) as reported by the Wilkinson Microwave Anisotropy Probe (WMAP) after their first year of observations exhibited statistically significant anomalies compared to…

Astrophysics · Physics 2008-11-26 Craig J. Copi , Dragan Huterer , Dominik J. Schwarz , Glenn D. Starkman

Recent analyses of the WMAP data have suggested that the low-order multipoles of the CMB anisotropy distribution show cosmologically interesting and unexpected morphologies and amplitudes. In this paper, we apply a power equalization (PE)…

Astrophysics · Physics 2009-11-10 P. Bielewicz , K. M. Gorski , A. J. Banday

We report an improved technique for diffuse foreground minimization from Cosmic Microwave Background (CMB) maps using a new multi-phase iterative internal-linear-combination (ILC) approach in harmonic space. The new procedure consists of…

Cosmology and Nongalactic Astrophysics · Physics 2017-09-18 Vipin Sudevan , Pavan K. Aluri , Sarvesh Kumar Yadav , Rajib Saha , Tarun Souradeep

We revisit the alignments of the largest structures observed in the cosmic microwave background (CMB) using the seven and nine-year WMAP and first-year Planck data releases. The observed alignments -- the quadrupole with the octopole and…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 Craig J. Copi , Dragan Huterer , Dominik J. Schwarz , Glenn D. Starkman

The method of correlation mapping on the full sphere is used to study the properties of the ILC map, as well as the dust and synchrotron background components. An anomalous correlation of the components with the ILC map in the main plane…

Cosmology and Nongalactic Astrophysics · Physics 2011-08-23 O. V. Verkhodanov , M. L. Khabibullina

We present a model-independent investigation of the WMAP data with respect to scale- dependent non-Gaussianities (NGs) by employing the method of constrained randomization. For generating so-called surrogate maps a shuffling scheme is…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 C. Raeth , A. J. Banday , G. Rossmanith , H. Modest , R. Suetterlin , K. M. Gorski , J. Delabrouille , G. E. Morfill

[Abridged] We apply the multipole vector framework to full-sky maps derived from the first year WMAP data. We significantly extend our earlier work showing that the two lowest cosmologically interesting multipoles, l=2 and 3, are not…

Astrophysics · Physics 2009-11-11 C. J. Copi , D. Huterer , D. J. Schwarz , G. D. Starkman

A detection or nondetection of primordial non-Gaussianity in the CMB data is essential not only to test alternative models of the physics of the early universe but also to discriminate among classes of inflationary models. Given this far…

Cosmology and Nongalactic Astrophysics · Physics 2010-09-15 A. Bernui , M. J. Reboucas

The Correlated Component Analysis (CCA) allows us to estimate how the different diffuse emissions mix in CMB experiments, exploiting also complementary information from other surveys. It is especially useful to deal with possible additional…

Astrophysics · Physics 2009-01-13 A. Bonaldi , S. Ricciardi , S. Leach , F. Stivoli , C. Baccigalupi , G. De Zotti

In this article we propose a novel test for statistical anisotropy of the CMB. The test is based on the fact, that the Galactic foregrounds have a remarcably strong symmetry with respect to their antipodal points and with respect to the…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-28 P. Naselsky , M. Hansen , J. Kim

We analyze whether there is any residual foreground contamination in the cleaned WMAP 7 years data for the differential assemblies, Q, V and W. We calculate the correlation between the foreground map, from which long wavelength correlations…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-11 Pravabati Chingangbam , Changbom Park

We examine statistical isotropy of large scale anisotropies of the Internal Linear Combination (ILC) map, based on three year WMAP data. Our study reveals no significant deviation from statistical isotropy on large angular scales of 3-year…

Astrophysics · Physics 2009-11-11 Amir Hajian , Tarun Souradeep

We present non-Gaussianity testing on recently-released derived maps from the first-year WMAP data by Tegmark, de Oliveria-Costa and Hamilton. Our test is based on a phase mapping technique which has the advantage of testing non-Gaussianity…

Astrophysics · Physics 2009-11-07 Lung-Yih Chiang , Pavel D. Naselsky , Oleg V. Verkhodanov , Michael J. Way
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