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We present the analysis on the quadrupole phases of the Internal Linear Combination map, ILC(I) and (III) derived by the WMAP team (1 and 3-year data release). This approach allows us to see the global trend of non-Gaussianity of the…

Astrophysics · Physics 2008-11-26 Pavel D. Naselsky , Oleg 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

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

[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 show that the popular ILC approach is unstable in respect to the division of the sample of map pixels to the set of ``homogeneous'' subsamples. For suitable choice of such subsamples we can obtain the restored CMB signal with amplitudes…

Cosmology and Nongalactic Astrophysics · Physics 2011-02-18 A. Doroshkevich , O. Verkhodanov

We study the alignments of the low multipoles of CMB anisotropies with specific directions in the sky (i.e. the dipole, the north Ecliptic pole, the north Galactic pole and the north Super Galactic pole). Performing $10^5$ random…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 Alessandro Gruppuso , Krzysztof M. Gorski

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

Residual error in calibration coefficients corresponding to observed CMB maps is an important issue while estimating a pure CMB signal. A component separation method, if these errors in the input foreground contaminated CMB maps are not…

Cosmology and Nongalactic Astrophysics · Physics 2020-10-21 Vipin Sudevan , Rajib Saha

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 investigate the large scale anomalies in the angular distribution of the cosmic microwave background radiation as measured by WMAP using several tests. These tests, based on the multipole vector expansion, measure correlations between…

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 are presenting an Internal Linear Combination (ILC) CMB map, in which the foreground is reduced through harmonic variance minimization. We have derived our method by converting a general form of pixel-space approach into spherical…

Astrophysics · Physics 2009-09-29 Jaiseung Kim , Pavel Naselsky , Per Rex Christensen

Component separation methods mitigate the cross-contamination between different extragalactic and galactic contributions to cosmic microwave background (CMB) data. This is often done by linearly combining CMB maps from different frequency…

Cosmology and Nongalactic Astrophysics · Physics 2026-02-26 Jack Y. L. Kwok , William R. Coulton , Niall MacCrann , Fiona McCarthy , Boris Bolliet , Blake D. Sherwin

We analyze the alignment of the low multipoles (quadrupole and octupole) of various maps of the WMAP 5yr release: the CMB maps obtained with ILC and MCMC methods, the CMB map in the V band after foreground reduction, and, for comparison,…

Cosmology and Nongalactic Astrophysics · Physics 2010-01-15 Alessandro Gruppuso , Carlo Burigana

We propose a new internal linear combination (ILC) method in the pixel space, applicable on large angular scales of the sky, to estimate a foreground minimized Cosmic Microwave Background (CMB) temperature anisotropy map by incorporating…

Cosmology and Nongalactic Astrophysics · Physics 2018-11-07 Vipin Sudevan , Rajib Saha

Cross-correlating the lensing signals of galaxies and comic microwave background (CMB) fluctuations is expected to provide valuable cosmological information. In particular it may help tighten constraints on parameters describing the…

Cosmology and Nongalactic Astrophysics · Physics 2017-09-14 Philipp M. Merkel , Bjoern Malte Schaefer

WMAP and Planck may have uncovered several anomalies in the full CMB sky that could indicate possible new physics driving the growth of density fluctuations in the early Universe. These include an unusually low power at the largest scales…

Cosmology and Nongalactic Astrophysics · Physics 2018-09-26 Fulvio Melia

We analyze the effect of foregrounds on the observed alignment of CMBR quadrupole and octopole. The alignment between these multipoles is studied by using a symmetry based approach which assigns a principal eigenvector (PEV) or an axis with…

Cosmology and Nongalactic Astrophysics · Physics 2011-10-03 Pavan K. Aluri , Pramoda K. Samal , Pankaj Jain , John. P. Ralston

The low multipole anomalies of the Cosmic Microwave Background has received much attention during the last few years. It is still not ascertained whether these anomalies are indeed primordial or the result of systematics or foregrounds. An…

Cosmology and Nongalactic Astrophysics · Physics 2012-11-01 M. Hansen , J. Kim , A. M. Frejsel , S. Ramazanov , P. Naselsky , W. Zhao , C. Burigana

The dipolar model \cite{Gordon:2005ai} has attracted much interest because it may phenomenologically explain the CMB hemispherical power asymmetry found in the WMAP and Planck data. Since such a model explicitly breaks isotropy at large…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-24 L. Polastri , A. Gruppuso , P. Natoli
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