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Related papers: Bianchi Type VII_h Models and the WMAP 3-year Data

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Motivated by the large-scale asymmetry observed in the cosmic microwave background sky, we consider a specific class of anisotropic cosmological models -- Bianchi type VII_h -- and compare them to the WMAP first-year data on large angular…

Astrophysics · Physics 2009-11-10 T. R. Jaffe , A. J. Banday , H. K. Eriksen , K. M. Gorski , F. K. Hansen

We investigate the effect of foreground residuals in the WMAP data (Bennet et al. 2004) by adding foreground contamination to Gaussian ensembles of CMB signal and noise maps. We evaluate a set of non-Gaussian estimators on the contaminated…

Astrophysics · Physics 2009-11-13 J. Medeiros , C. R. Contaldi

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

Bianchi VII_h models have been recently proposed to explain potential anomalies in the CMB anisotropy as observed by WMAP. We investigate the violation of statistical isotropy due to an embedded Bianchi VII_h templates in the CMB anisotropy…

Astrophysics · Physics 2008-11-26 Tuhin Ghosh , Amir Hajian , Tarun Souradeep

We explore methods of fitting templates to cosmic microwave background (CMB) data, and in particular demonstrate the application of the total convolver algorithm as a fast method of performing a search over all possible locations and…

Astrophysics · Physics 2009-11-11 T. R. Jaffe , A. J. Banday , H. K. Eriksen , K. M. Gorski , F. K. Hansen

We measured the cross-correlation of the Wilkinson Microwave Anisotropy Probe (WMAP) 7 year temperature map and the full sky data release of the Wide-field Infrared Survey Explorer (WISE) galaxy map. Using careful mapmaking and masking…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 András Kovács , István Szapudi , Benjamin R. Granett , Zsolt Frei

We apply a previously developed Gibbs sampling framework to the foreground corrected 3-yr WMAP polarization data and compute the power spectrum and residual foreground template amplitude posterior distributions. We first analyze the…

Many of the current anomalies reported in the Wilkinson Microwave Anisotropy Probe (WMAP) 1-year data disappear after `correcting' for the best-fit embedded Bianchi type VII_h component (Jaffe et al. 2005), albeit assuming no dark energy…

Astrophysics · Physics 2009-09-29 J. D. McEwen , M. P. Hobson , A. N. Lasenby , D. J. Mortlock

[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 perform a definitive analysis of Bianchi VII_h cosmologies with WMAP observations of the cosmic microwave background (CMB) temperature anisotropies. Bayesian analysis techniques are developed to study anisotropic cosmologies using…

Cosmology and Nongalactic Astrophysics · Physics 2013-12-04 J. D. McEwen , T. Josset , S. M. Feeney , H. V. Peiris , A. N. Lasenby

In this paper, we present a foreground analysis of the WMAP 5-year data using the FASTICA algorithm, improving on the treatment of the WMAP 3-year data in Bottino et al 2008. We revisit the nature of the free-free spectrum with the emphasis…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-14 M. Bottino , A. J. Banday , D. Maino

The WMAP satellite has completed 3 years of observations of the cosmic microwave background radiation. The 3-year data products include several sets of full sky maps of the Stokes I, Q and U parameters in 5 frequency bands, spanning 23 to…

Using a Gibbs sampling algorithm for joint CMB estimation and component separation, we compute the large-scale CMB and foreground posteriors of the 3-yr WMAP temperature data. Our parametric data model includes the cosmological CMB signal…

Astrophysics · Physics 2010-11-11 H. K. Eriksen , C. Dickinson , J. B. Jewell , A. J. Banday , K. M. Gorski , C. R. Lawrence

We study the spectral and morphological characteristics of the diffuse Galactic emission in the WMAP temperature data using a template-based multi-linear regression, and obtain the following results. 1. We confirm previous observations of a…

Astrophysics · Physics 2009-06-23 Gregory Dobler , Douglas P. Finkbeiner

Motivated by the success of the Bianchi VII_h model in addressing many of the anomalies observed in the WMAP data (Jaffe et al.), we present calculations in real and in wavelet space of the Higher Criticism statistic of the Bianchi…

Astrophysics · Physics 2009-11-11 L. Cayon , A. J. Banday , T. Jaffe , H. K. Eriksen , F. K. Hansen , K. M. Gorski , J. Jin

We present an analysis of the foreground emission present in the WMAP 3-year data as determined by the method of Independent Component Analysis. We derived coupling coefficients between the WMAP data and foreground templates which are then…

Astrophysics · Physics 2008-07-14 M. Bottino , A. J. Banday , D. Maino

We have extended the analysis of Jaffe et al. to a complete Markov chain Monte Carlo (MCMC) study of the Bianchi type ${\rm VII_h}$ models including a dark energy density, using 1-year and 3-year Wilkinson Microwave Anisotropy Probe (WMAP)…

Astrophysics · Physics 2008-11-26 M. Bridges , J. D. McEwen , A. N. Lasenby , M. P. Hobson

WMAP data when combined with ancillary data on free-free, synchrotron and dust allow an improved understanding of the spectrum of emission from each of these components. Here we examine the sky variation at intermediate and high latitudes…

Cosmology and Nongalactic Astrophysics · Physics 2013-09-27 Tuhin Ghosh , A. J. Banday , Tess Jaffe , Clive Dickinson , Rod Davies , Richard Davis , Krzysztof Gorski

We generalize the predictions for the CMB anisotropy patterns arising in Bianchi type VIIh universes to include a dark energy component. We consider these models in light of the result of Jaffe et al. (2005a,b) in which a correlation was…

Astrophysics · Physics 2009-11-13 T. R. Jaffe , S. Hervik , A. J. Banday , K. M. Gorski

We develop a new Bayesian method for estimating white noise levels in CMB sky maps, and apply this algorithm to the 5-year WMAP data. We assume that the amplitude of the noise RMS is scaled by a constant value, alpha, relative to a…

Cosmology and Nongalactic Astrophysics · Physics 2009-08-24 N. E. Groeneboom , H. K. Eriksen , K. Gorski , G. Huey , J. Jewell , B. Wandelt
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