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Related papers: Foreground analysis from the 1-year Wilkinson Micr…

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Angular power spectrum of the cosmic microwave background (CMB) temperature anisotropies is one of the most important on characteristics of the Universe such as its geometry and total density. Using flat sky approximation and Fourier…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-30 Lung-Yih Chiang , Fei-Fan Chen

We describe a sampling method to estimate the polarized CMB signal from observed maps of the sky. We use a Metropolis-within-Gibbs algorithm to estimate the polarized CMB map, containing Q and U Stokes parameters at each pixel, and its…

We generate simulations of the CMB temperature field as observed by the WMAP satellite, taking into account the detailed shape of the asymmetric beams and scanning strategy of the experiment, and use these to re-estimate the WMAP beam…

Cosmology and Nongalactic Astrophysics · Physics 2012-02-02 Ingunn Kathrine Wehus , Lotty Ackerman , H. K. Eriksen , Nicolaas E. Groeneboom

Cosmology and other scientific results from the WMAP mission require an accurate knowledge of the beam patterns in flight. While the degree of beam knowledge for the WMAP one-year and three-year results was unprecedented for a CMB…

We implement and investigate a method for measuring departures from scale-invariance, both scale-dependent as well as scale-free, in the primordial power spectrum of density perturbations using cosmic microwave background (CMB) C_l data and…

Astrophysics · Physics 2009-11-11 Samuel Leach

We studied the WMAP temperature anisotropy data using two different methods. The derived signal gradient maps show regions with low mean gradients in structures near the ecliptic poles and higher gradient values in the wide ecliptic…

Astrophysics · Physics 2007-05-23 K. T. Chyzy , B. Novosyadlyj , M. Ostrowski

Cosmic microwave background (CMB) radiation data obtained by different experiments contain, besides the desired signal, a superposition of microwave sky contributions. We present a fast and robust method, using a wavelet decomposition on…

Cosmology and Nongalactic Astrophysics · Physics 2013-05-24 R. Fernández-Cobos , P. Vielva , R. B. Barreiro , E. Martínez-González

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

In these proceedings, we discuss the extraction, in WMAP 5 year data, of a clean CMB map, of foreground emission (dominated by emission of the interstellar medium of our galaxy), and of the tiny signal from Sunyaev Zel'dovich effect in the…

Cosmology and Nongalactic Astrophysics · Physics 2010-06-29 Jacques Delabrouille

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

We present results from the QMAP balloon experiment, which maps the Cosmic Microwave Background (CMB) and probes its angular power spectrum on degree scales. In two separate flights, data were taken in six channels at two frequency bands…

Recent fits of cosmological parameters by the Wilkinson Microwave Anisotropy Probe (WMAP) measurement favor a primordial scalar spectrum with varying index. This result, if stands, could severely constrain inflation model buildings. Most…

Astrophysics · Physics 2008-11-26 Bo Feng , Mingzhe Li , Ren-Jie Zhang , Xinmin Zhang

The Wilkinson Microwave Anisotropy Probe microwave background data may be giving us clues about new physics at the transition from a ``stringy'' epoch of the universe to the standard Friedmann Robertson Walker description. Deviations on…

High Energy Physics - Phenomenology · Physics 2009-11-10 Mar Bastero-Gil , Katherine Freese , Laura Mersini-Houghton

We extend to large scales a method proposed in previous work that reconstructs non-parametrically the primordial power spectrum from cosmic microwave background data at high resolution. The improvement is necessary to account for the…

Astrophysics · Physics 2009-11-13 Domenico Tocchini-Valentini , Yehuda Hoffman , Joseph Silk

We present a novel estimate of the cosmological microwave background (CMB) map by combining the two latest full-sky microwave surveys: WMAP nine-year and Planck PR1. The joint processing benefits from a recently introduced component…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-18 J. Bobin , F. Sureau , J. -L. Starck , A. Rassat , P. Paykari

We develop a novel method to separate the components of a diffuse emission process based on an association with the energy spectra. Most of the existing methods use some information about the spatial distribution of components, e.g.,…

Instrumentation and Methods for Astrophysics · Physics 2012-02-07 Dmitry Malyshev

In cosmic microwave background (CMB) experiments, foreground-cleaned temperature maps are still contaminated by the residual dipole due to uncertainties of the Doppler dipole direction and microwave radiometer sidelobe. To obtain reliable…

Cosmology and Nongalactic Astrophysics · Physics 2013-01-16 Hao Liu , Ti-Pei Li

We have independently measured the genus topology of the temperature fluctuations in the cosmic microwave background seen by the Wilkinson Microwave Anisotropy Probe (WMAP). A genus analysis of the WMAP data indicates consistency with…

Astrophysics · Physics 2011-05-10 Wesley N. Colley , J. Richard Gott

In order to extract cosmological information from observations of the millimeter and submillimeter sky, foreground components must first be removed to produce an estimate of the cosmic microwave background (CMB). We developed a…

Cosmology and Nongalactic Astrophysics · Physics 2020-11-10 Matthew A. Petroff , Graeme E. Addison , Charles L. Bennett , Janet L. Weiland

The statistical expectation values of the temperature fluctuations of cosmic microwave background (CMB) are assumed to be preserved under rotations of the sky. We investigate the statistical isotropy of the CMB anisotropy maps recently…

Astrophysics · Physics 2007-05-23 Tarun Souradeep , Amir Hajian
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