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Related papers: Phase cross-correlation of the WMAP ILC map and fo…

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Although the ``internal linear'' combination method (ILC) is a technique widely used for the separation of the Cosmic Microwave Background signal from the Galactic foregrounds, its characteristics are not yet well defined. This can lead to…

Cosmology and Nongalactic Astrophysics · Physics 2009-10-23 R. Vio , P. Andreani

We measure the 2-1 cumulant correlator power spectrum $C^{21}_l$, a degenerate bispectrum, from the second data release of the Wilkinson Microwave Anisotropy Probe (WMAP). Our high resolution measurements with SpICE span a large…

Astrophysics · Physics 2009-11-11 Gang Chen , Istvan Szapudi

We test the hypothesis that the temperature of the cosmic microwave background is consistent with a Gaussian random field defined on the celestial sphere, using de-biased internal linear combination (DILC) map produced from the 3-year WMAP…

Astrophysics · Physics 2010-11-11 Lung-Yih Chiang , Pavel D. Naselsky , Peter Coles

If the principle of statistical isotropy is valid, then the angular power spectrum (APS) of cosmic microwave background (CMB) radiation is uncorrelated between different multipoles. We propose a novel technique to analyse any possible…

Cosmology and Nongalactic Astrophysics · Physics 2022-12-29 Md Ishaque Khan , Rajib Saha

We quantify the level of foreground contamination in the QMAP Cosmic Microwave Background (CMB) data with two objectives: (a) measuring the level to which the QMAP power spectrum measurements need to be corrected for foregrounds and (b)…

Most analysis of Cosmic Microwave Background spherical harmonic coefficients a_lm has focused on estimating the power spectrum C_l=<|a_lm|^2> rather than the coefficients themselves. We present a minimum-variance method for measuring a_lm…

Astrophysics · Physics 2009-10-07 Angelica de Oliveira-Costa , Max Tegmark

We test the hemispherical power asymmetry of the WMAP 7-year low-resolution temperature and polarization maps. We consider two natural estimators for such an asymmetry and exploit our implementation of an optimal angular power spectrum…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 F. Paci , A. Gruppuso , F. Finelli , A. De Rosa , N. Mandolesi , P. Natoli

We examine the consistency of WMAP9 and Planck data. We compare sky maps, power spectra, and inferred LCDM cosmological parameters. Residual dipoles are seen in the WMAP and Planck sky map differences, but are consistent within the…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-30 D. Larson , J. L. Weiland , G. Hinshaw , C. L. Bennett

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 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

A considerable effort has recently gone into the study of Gaussianity of cosmic microwave background (CMB) data. Among such attempts, there is one with two non-Gaussianity indicators, proposed by the authors, and used in a search for…

Cosmology and Nongalactic Astrophysics · Physics 2009-07-10 A. Bernui , M. J. Reboucas

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

We propose two detection techniques that take advantage of a small sky area approximation and are based on modifications of the "internal linear combination" (ILC) method, an approach widely used in Cosmology for the separation of the…

Instrumentation and Methods for Astrophysics · Physics 2012-06-21 R. Vio , P. Andreani , E. P. R. G. Ramos , A. da Silva

We employ the one-dimensional Fourier representation (1DFR) to analyze the 3-year WMAP de-biased internal linear combination (DILC) map and its possible contamination by galactic foregrounds. The 1DFR is a representation of the spherical…

Astrophysics · Physics 2010-10-27 Lung-Yih Chiang , Peter Coles , Pavel D Naselsky , Poul Olesen

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 recent data release of ESA's Planck mission together with earlier WMAP releases provide the first opportunity to compare high resolution full sky Cosmic Microwave Background temperature anisotropy maps. To quantify the coherence of…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-16 András Kovács , Julien Carron , István Szapudi

We search for planar deviations of statistical isotropy in the Wilkinson Microwave Anisotropy Probe (WMAP) data by applying a recently introduced angular-planar statistics both to full-sky and to masked temperature maps, including in our…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 L. Raul Abramo , Armando Bernui , Thiago S. Pereira

We measure the angular power spectrum of the WMAP first-year temperature anisotropy maps. We use SpICE (Spatially Inhomogeneous Correlation Estimator) to estimate Cl's for multipoles l=2-900 from all possible cross-correlation channels.…

Astrophysics · Physics 2009-11-10 Pablo Fosalba , Istvan Szapudi

We investigate a possible asymmetry in the statistical properties of the cosmic microwave background temperature field and to do so we construct an estimator aiming at detecting a dipolar modulation. Such a modulation is found to induce…

Astrophysics · Physics 2009-11-10 Simon Prunet , Jean-Philippe Uzan , Francis Bernardeau , Tristan Brunier

We present a new estimate of foreground emission in the WMAP data, using a Markov chain Monte Carlo (MCMC) method. The new technique delivers maps of each foreground component for a variety of foreground models, error estimates of the…