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The WMAP satellite has made available high quality maps of the sky in five frequency bands ranging from 22 to 94 GHz, with the main scientific objective of studying the anisotropies of the Cosmic Microwave Background (CMB). These maps,…

Astrophysics · Physics 2009-11-13 J. Delabrouille , J. -F. Cardoso , M. Le Jeune , M. Betoule , G. Fay , F. Guilloux

We prepare real-life Cosmic Microwave Background (CMB) lensing extraction with the forthcoming Planck satellite data, by studying two systematic effects related to the foregrounds contamination: the impact of foreground residuals after a…

Cosmology and Nongalactic Astrophysics · Physics 2009-11-12 L. Perotto , J. Bobin , S. Plaszczynski , J. -L. Starck , A. Lavabre

HI intensity mapping is an emerging tool to probe dark energy. Observations of the redshifted HI signal will be contaminated by instrumental noise, atmospheric and Galactic foregrounds. The latter is expected to be four orders of magnitude…

Cosmology and Nongalactic Astrophysics · Physics 2015-10-28 M. -A. Bigot-Sazy , C. Dickinson , R. A. Battye , I. W. A. Browne , Y. -Z. Ma , B. Maffei , F. Noviello , M. Remazeilles , P. N. Wilkinson

Neutral hydrogen intensity mapping can in principle deliver rapid and large-volume cosmological surveys with exquisitely accurate redshifts that are determined directly from imaging. However, intensity maps suffer from very strong…

Cosmology and Nongalactic Astrophysics · Physics 2024-05-30 Rahul Kothari , Roy Maartens

We extend the internal template foreground removal method by accounting for spatially varying spectral parameters such as the spectral indices of synchrotron and dust emission and the dust temperature. As the previous algorithm had to…

Cosmology and Nongalactic Astrophysics · Physics 2019-02-04 Kiyotomo Ichiki , Hiroaki Kanai , Nobuhiko Katayama , Eiichiro Komatsu

Numerous fields of nonlinear physics, very different in nature, produce signals and images, that share the common feature of being essentially constituted of piecewise homogeneous phases. Analyzing signals and images from corresponding…

Data Analysis, Statistics and Probability · Physics 2020-06-17 Barbara Pascal , Nelly Pustelnik , Patrice Abry , Jean-Christophe Géminard , Valérie Vidal

Estimation of the sky signal from sequences of time ordered data is one of the key steps in Cosmic Microwave Background (CMB) data analysis, commonly referred to as the map-making problem. Some of the most popular and general methods…

Cosmology and Nongalactic Astrophysics · Physics 2014-12-16 Mikolaj Szydlarski , Laura Grigori , Radek Stompor

Separating galactic foreground emission from maps of the cosmic microwave background (CMB), and quantifying the uncertainty in the CMB maps due to errors in foreground separation are important for avoiding biases in scientific conclusions.…

Instrumentation and Methods for Astrophysics · Physics 2020-11-11 K. Aylor , M. Haq , L. Knox , Y. Hezaveh , L. Perreault-Levasseur

A flexible maximum-entropy component separation algorithm is presented that accommodates anisotropic noise, incomplete sky-coverage and uncertainties in the spectral parameters of foregrounds. The capabilities of the method are determined…

The internal linear combination (ILC) method is a popular approach for constructing component-separated maps in cosmic microwave background (CMB) analyses. It optimally combines observed maps at different frequencies to produce an unbiased…

Cosmology and Nongalactic Astrophysics · Physics 2024-03-05 Kristen M. Surrao , J. Colin Hill

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 study the Internal Linear Combination (ILC) method presented by the Wilkinson Microwave Anisotropy Probe (WMAP) science team, with the goal of determining whether it may be used for cosmological purposes, as a template-free alternative…

Astrophysics · Physics 2009-07-09 H. K. Eriksen , A. J. Banday , K. M. Gorski , P. B. Lilje

The atmosphere is one of the most important contamination sources in the ground-based Cosmic Microwave Background (CMB) observations. In this paper, we study three kinds of filters, which are polynomial filter, high-pass filter, and Wiener…

Cosmology and Nongalactic Astrophysics · Physics 2023-04-26 Yi-Wen Wu , SiYu Li , Yang Liu , Zirui Zhang , Hao Liu , Hong Li

The Cosmic Microwave Background anisotropies are difficult to measure at large angular scales. In this paper, we present a new analysis of the \Planck\ High Frequency Instrument data that brings the cosmological part and its major…

Cosmology and Nongalactic Astrophysics · Physics 2021-06-09 J. -M. Delouis , J. -L. Puget , L. Vibert

Stochastic gravitational-wave backgrounds can be of either cosmological or astrophysical origin. The detection of an astrophysical stochastic gravitational-wave background with ground-based interferometers is expected in the near future.…

General Relativity and Quantum Cosmology · Physics 2024-10-01 Haowen Zhong , Bei Zhou , Luca Reali , Emanuele Berti , Vuk Mandic

In the context of maximum-likelihood parametric component separation for next-generation full-sky CMB polarization experiments, we study the impact of fitting different spectral parameters of Galactic foregrounds in distinct subsets of…

Cosmology and Nongalactic Astrophysics · Physics 2025-10-14 Arianna Rizzieri , Clément Leloup , Josquin Errard , Davide Poletti

Galactic foregrounds are the main obstacle to observations of the cosmic microwave background (CMB) $B$-mode polarization. In addition to obscuring the inflationary $B$-mode signal by several orders of magnitude, Galactic foregrounds have…

Cosmology and Nongalactic Astrophysics · Physics 2021-03-17 Mathieu Remazeilles , Aditya Rotti , Jens Chluba

We study the effects of astrophysical foregrounds on the ability of CMB B-mode polarization experiments to constrain the primordial tensor-to-scalar ratio, r. To clean the foreground contributions we use parametric, maximum likelihood…

Cosmology and Nongalactic Astrophysics · Physics 2012-04-20 Josquin Errard , Radek Stompor

The detection of point-sources in microwave maps is a critical step in the analysis of the Cosmic Microwave Background (CMB) data. If not properly removed, these sources have adverse effects on the estimation of the power-spectrum and/or…

Astrophysics · Physics 2009-07-14 R. Vio , P. Andreani

Most work on foreground removal has treated the case where the frequency dependence of all components is perfectly known and independent of position. In contrast, real-world foregrounds are generally not perfectly correlated between…

Astrophysics · Physics 2009-10-30 Max Tegmark
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