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Related papers: Phase statistics of the WMAP 7 year data

200 papers

The detection of non-Gaussianity in the CMB data would rule out a number of inflationary models. A null detection of non-Gaussianity, instead, would exclude alternative models for the early universe. Thus, a detection or non-detection of…

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

Probing Gaussianity represents one of the key questions in modern cosmology, because it allows to discriminate between different models of inflation. We test for large-scale non-Gaussianities in the cosmic microwave background (CMB) in a…

Cosmology and Nongalactic Astrophysics · Physics 2010-05-17 C. Raeth , G. Rossmanith , G. Morfill , A. J. Banday , K. M. Gorski

We repeat the directional spherical real Morlet wavelet analysis used to detect non-Gaussianity in the WMAP 1-year data (McEwen et al. 2005a), on the WMAP 3-year data. The non-Gaussian signal previously detected is indeed present in the…

Astrophysics · Physics 2011-02-11 J. D. McEwen , M. P. Hobson , A. N. Lasenby , D. J. Mortlock

The three Minkowski functionals and the recently defined length of the skeleton are estimated for the co-added first-year Wilkinson Microwave Anisotropy Probe (WMAP) data and compared with 5000 Monte Carlo simulations, based on Gaussian…

Astrophysics · Physics 2008-11-26 H. K. Eriksen , D. I. Novikov , P. B. Lilje , A. J. Banday , K. M. Gorski

(Abridged) New full sky temperature and polarization maps based on seven years of data from WMAP are presented. The new results are consistent with previous results, but have improved due to reduced noise from the additional integration…

The identification and extraction of non-Gaussian signals is one of the main cosmological challenges facing future experimental measurements of the cosmic microwave background temperature pattern. We present a generalized statistical…

Astrophysics · Physics 2009-11-07 Lung-Yih Chiang , Pavel Naselsky , Peter Coles

We propose a set of statistics $S_q$ for detecting non-gaussianity in CMBR anisotropy data sets. These statistics are both simple and, according to calculations over a space of linear combinations of three-point functions, nearly optimal at…

High Energy Physics - Phenomenology · Physics 2007-05-23 Paul Graham , Neil Turok , Philip Lubin , Jeff Schuster

We present measurements of the clustering of hot and cold patches in the microwave background sky as measured from the Wilkinson Microwave Anisotropy Probe (WMAP) five-year data. These measurements are compared with theoretical predictions…

Cosmology and Nongalactic Astrophysics · Physics 2009-06-12 Graziano Rossi , Ravi K. Sheth , Changbom Park , Carlos Hernandez-Monteagudo

In order to test for non-Gaussianities with respect to scale-dependencies we use so-called surrogate maps, in which possible phase correlations of the Fourier phases of the original WMAP data and simulations, respectively, are destroyed by…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-11 H. I. Modest , C. Räth , A. J. Banday , G. Rossmanith , R. Sütterlin , S. Basak , J. Delabrouille , K. M. Górski , G. E. Morfill

We forecast constraints on primordial non-Gaussianity achievable from forthcoming surveys by exploiting the scale-dependent halo bias introduced on large scales by non-Gaussian initial conditions. We explore the performance of exploiting…

Astrophysics · Physics 2010-03-26 Carmelita Carbone , Licia Verde , Sabino Matarrese

[Abridged] We present updated estimates of Galactic foreground emission using seven years of WMAP data. Using the power spectrum of differences between multi-frequency template-cleaned maps, we find no evidence for foreground contamination…

We use the statistics of regions above or below a temperature threshold (excursion sets) to study the cosmic microwave background (CMB) anisotropy in models with primordial non-Gaussianity of the local type. By computing the full-sky…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 Graziano Rossi , Pravabati Chingangbam , Changbom Park

Combined analyses of WMAP 3-year and ACBAR Cosmic Microwave Anisotropies angular power spectra have presented evidence for gravitational lensing >3 sigma level. This signal could provide a relevant test for cosmology. After evaluating and…

The Wilkinson Microwave Anisotropy Probe WMAP has mapped the entire sky in five frequency bands between 23 and 94 GHz with polarization sensitive radiometers. We present three-year full-sky maps of the polarization and analyze them for…

We test the consistency of estimates of the non-linear coupling constant f_{NL} using non-Gaussian CMB maps generated by the method described in (Liguori, Matarrese and Moscardini 2003). This procedure to obtain non-Gaussian maps differs…

Astrophysics · Physics 2009-11-10 P. Cabella , M. Liguori , F. K. Hansen , D. Marinucci , S. Matarrese , L. Moscardini , N. Vittorio

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

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

In this work we present constraints on different shapes of primordial non-Gaussianity using the Wilkinson Microwave Anisotropy Probe (WMAP) 7-year data and the spherical Mexican hat wavelet fnl estimator including the linear term…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-03 A. Curto , E. Martinez-Gonzalez , R. B. Barreiro

The primordial non-Gaussian parameter fNL has been shown to be scale-dependent in several models of inflation with a variable speed of sound. Starting from a simple ansatz for a scale-dependent amplitude of the primordial curvature…

Cosmology and Nongalactic Astrophysics · Physics 2010-01-06 Emiliano Sefusatti , Michele Liguori , Amit P. S. Yadav , Mark G. Jackson , Enrico Pajer

We investigate whether a Gaussian likelihood, as routinely assumed in the analysis of cosmological data, is supported by simulated survey data. We define test statistics, based on a novel method that first destroys Gaussian correlations in…

Cosmology and Nongalactic Astrophysics · Physics 2017-11-15 Elena Sellentin , Alan F. Heavens