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We present the first results from a Bayesian analysis of the WMAP first year data using a Gibbs sampling technique. Using two independent, parallel supercomputer codes we analyze the WMAP Q, V and W bands. The analysis results in a full…

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 estimate CMB polarization and temperature power spectra using WMAP 5-year foreground contaminated maps. The power spectrum is estimated by using a model independent method, which does not utilize directly the diffuse foreground templates…

Cosmology and Nongalactic Astrophysics · Physics 2011-02-11 Pramoda Kumar Samal , Rajib Saha , Jacques Delabrouille , Simon Prunet , Pankaj Jain , Tarun Souradeep

A well-tested and validated Gibbs sampling code, that performs component separation and CMB power spectrum estimation, was applied to the {\it WMAP} 5-yr data. Using a simple model consisting of CMB, noise, monopoles and dipoles, a ``per…

Cosmology and Nongalactic Astrophysics · Physics 2009-11-05 C. Dickinson , H. K. Eriksen , A. J. Banday , J. B. Jewell , K. M. Gorski , G. Huey , C. R. Lawrence , I. J. O'Dwyer , B. D. Wandelt

We revisit a recently introduced power spectrum estimation technique based on Gibbs sampling, with the goal of applying it to the high-resolution WMAP data. In order to facilitate this analysis, a number of sophistications have to be…

We analyze the three-year WMAP temperature anisotropy data seeking to confirm the power spectrum and likelihoods published by the WMAP team. We apply five independent implementations of four algorithms to the power spectrum estimation and…

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 use Bayesian component estimation methods to examine the prospects for large-scale polarized map and cosmological parameter estimation with simulated Planck data assuming simplified white noise properties. The sky signal is parametrized…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 Charmaine Armitage-Caplan , Joanna Dunkley , Hans Kristian Eriksen , Clive Dickinson

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 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 describe and implement an exact, flexible, and computationally efficient algorithm for joint component separation and CMB power spectrum estimation, building on a Gibbs sampling framework. Two essential new features are 1) conditional…

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

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 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)…

We estimate Cosmic Microwave Background (CMB) polarisation power spectra, and temperature-polarisation cross-spectra, from the 9-year data of the Wilkinson Microwave Anisotropy Probe (WMAP). Foreground cleaning is implemented using minimum…

Cosmology and Nongalactic Astrophysics · Physics 2016-03-02 Soumen Basak , Jacques Delabrouille

(Abridged) We present the angular power spectra derived from the 7-year maps and discuss the cosmological conclusions that can be inferred from WMAP data alone. The third acoustic peak in the TT spectrum is now well measured by WMAP. In the…

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

In this paper we estimate diffuse foreground minimized Cosmic Microwave Background (CMB) Stokes Q and U polarization maps based upon the fundamental concept of Gaussian nature of CMB and strong non-Gaussian nature of astrophysical polarized…

Cosmology and Nongalactic Astrophysics · Physics 2017-07-10 Ujjal Purkayastha , Rajib Saha

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

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 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
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