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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

This introductory guide aims to provide insight to new researchers in the field of cosmic microwave background (CMB) map analysis on best practices for several common procedures. We will discuss common map-modifying procedures such as…

Cosmology and Nongalactic Astrophysics · Physics 2024-12-02 Raelyn Marguerite Sullivan , Lukas Tobias Hergt , Douglas Scott

Spectral distortion anisotropies of the cosmic microwave background (CMB) provide a new probe of the early Universe that can be accessed using traditional CMB imaging techniques. It is possible to compute the creation and evolution of…

Cosmology and Nongalactic Astrophysics · Physics 2026-02-17 Jens Chluba , Sara Evangelista , Tom Daman , Geoff Vasil

Multi-frequency observations are needed to separate the CMB from foregrounds and accurately extract cosmological information from the data. The Analytical Blind Separation (ABS) method is dedicated to extracting the CMB power spectrum from…

Cosmology and Nongalactic Astrophysics · Physics 2021-03-22 Larissa Santos , Jian Yao , Le Zhang , Shamik Ghosh , Pengjie Zhang , Wen Zhao , Thyrso Villela , Jiming Chen , Jacques Delabrouille

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

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

As confusion with lensing B-modes begins to limit experiments that search for primordial B-mode polarization, robust methods for delensing the CMB polarization sky are becoming increasingly important. We investigate in detail the…

Cosmology and Nongalactic Astrophysics · Physics 2015-08-19 Blake D. Sherwin , Marcel Schmittfull

We analyze the spectrum of cosmic microwave background (CMB) anisotropies in the timescape cosmology: a potentially viable alternative to homogeneous isotropic cosmologies without dark energy. We exploit the fact that the timescape…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-18 M. Ahsan Nazer , David L. Wiltshire

In inflationary models, gravitational waves are produced and generate B-type polarization in the CMB. Since B polarization is only generated by gravity waves it does not suffer from the cosmic variance. A perfect decomposition of the CMB…

Astrophysics · Physics 2009-11-13 Mihail Amarie , Christopher Hirata , Uros Seljak

We discuss the problem of CMB spectrum corruption during Galactic emission removing. A new technique of spatial--frequency data reduction is proposed. The technique gives us a possibility to avoid a spatial harmonics nonorthogonality. The…

Astrophysics · Physics 2007-05-23 A. A. Brukhanov , D. P. Skulachev , I. A. Strukov , T. V. Konkina

We report here the first full sky component separation and CMB power spectrum estimation using a Wiener filtering technique on simulated data from the upcoming MAP experiment, set to launch in early 2001. The simulations included…

Astrophysics · Physics 2009-10-31 S. Prunet , R. Teyssier , S. T. Scully , F. R. Bouchet , R. Gispert

The delensing procedure is an effective tool for removing lensing-induced $B$-mode polarization in the Cosmic Microwave Background to allow for deep searches of primordial $B$-modes. However, the delensing algorithm existing in the…

Cosmology and Nongalactic Astrophysics · Physics 2011-03-01 Wei-Hsiang Teng , Chao-Lin Kuo , Jiun-Huei Proty Wu

We apply a messenger field method to solve the linear minimum-variance mapmaking equation in the context of Cosmic Microwave Background (CMB) observations. In simulations, the method produces sky maps that converge significantly faster than…

Instrumentation and Methods for Astrophysics · Physics 2018-01-24 Kevin M. Huffenberger , Sigurd K. Næss

We investigate two possible explanations for the large-angle anomalies in the Cosmic Microwave Background (CMB): an intrinsically anisotropic model and an inhomogeneous model. We take as an example of the former a Bianchi model (which…

Astrophysics · Physics 2009-11-13 Kate Land , Joao Magueijo

The detection of Cosmic Microwave Background primordial $B$-mode polarization would constitute a ``smoking gun" signal of primordial gravitational waves. However, this measurement requires accurate removal of polarized Galactic foregrounds…

Cosmology and Nongalactic Astrophysics · Physics 2026-03-18 Luca Gomez Bachar , Cora Dvorkin , Alberto Daniel Supanitsky

The recent measurements of the power spectrum of Cosmic Microwave Background anisotropies are consistent with the simplest inflationary scenario and big bang nucleosynthesis constraints. However, these results rely on the assumption of a…

The Quadratic Maximum Likelihood estimator can be used to reconstruct the Cosmic Microwave Background (CMB) power spectra with minimal error bars. Still, it requires an accurate estimate of the datasets noise covariance matrix in order to…

Cosmology and Nongalactic Astrophysics · Physics 2018-11-28 S. Vanneste , S. Henrot-Versillé , T. Louis , M. Tristram

Point-source contamination in high-precision Cosmic Microwave Background (CMB) maps severely affects the precision of cosmological parameter estimates. Among the methods that have been proposed for source detection, wavelet techniques based…

Astrophysics · Physics 2009-11-07 R. Vio , L. Tenorio , W. Wamsteker

We apply the Gabor transform methodology proposed in (Hansen et al. 2002, 2003) to the WMAP data in order to test the statistical properties of the CMB fluctuation field and specifically to evaluate the fundamental assumption of…

Astrophysics · Physics 2009-05-29 F. K. Hansen , A. J. Banday , K. M. Gorski

Breakdown of rotational invariance of the primordial power spectrum manifests in the statistical anisotropy of the observed Cosmic Microwave Background (CMB) radiation. Hemispherical power asymmetry in the CMB may be caused due to a dipolar…

Cosmology and Nongalactic Astrophysics · Physics 2023-05-23 Md Ishaque Khan , Rajib Saha
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