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相关论文: Fast CMB Analyses via Correlation Functions

200 篇论文

We use an optimal estimator to study the variance of the WMAP 9 CMB field at low resolution, in both temperature and polarization. Employing realistic Monte Carlo simulation, we find statistically significant deviations from the…

宇宙学与河外天体物理 · 物理学 2015-06-15 A. Gruppuso , P. Natoli , F. Paci , F. Finelli , D. Molinari , A. De Rosa , N. Mandolesi

We update the search for features, due to transient reductions in inflaton's speed of sound, in the Cosmic Microwave Background (CMB) angular power spectrum using Planck 2018 temperature, polarization and lensing data. We develop a new…

宇宙学与河外天体物理 · 物理学 2021-06-23 Guadalupe Cañas-Herrera , Jesús Torrado , Ana Achúcarro

CMB and lensing reconstruction power spectra are powerful probes of cosmology. However they are correlated, since the CMB power spectra are lensed and the lensing reconstruction is constructed using CMB multipoles. We perform a full…

宇宙学与河外天体物理 · 物理学 2017-03-20 Julien Peloton , Marcel Schmittfull , Antony Lewis , Julien Carron , Oliver Zahn

In this paper we demonstrate an efficient method for including both CMB temperature and polarisation data in optimal non-Gaussian estimators. The method relies on orthogonalising the multipoles of the temperature and polarisation maps and…

宇宙学与河外天体物理 · 物理学 2014-09-05 J. R. Fergusson

Accurate measurements of angular power spectrum of Cosmic Microwave Background (CMB) radiation has lead to marked improvement in the estimates of different cosmological parameters. This has required removal of foreground contamination as…

天体物理学 · 物理学 2009-11-13 Rajib Saha , Pankaj Jain , Tarun Souradeep

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…

宇宙学与河外天体物理 · 物理学 2015-05-30 Lung-Yih Chiang , Fei-Fan Chen

We present a method to delens the acoustic peaks of the CMB temperature and polarization power spectra internally, using lensing maps reconstructed from the CMB itself. We find that when delensing CMB acoustic peaks with a lensing potential…

宇宙学与河外天体物理 · 物理学 2017-05-31 Neelima Sehgal , Mathew S. Madhavacheril , Blake Sherwin , Alexander van Engelen

Microwave background temperature and polarization observations are a powerful way to constrain cosmological parameters if the likelihood function can be calculated accurately. The temperature and polarization fields are correlated, partial…

天体物理学 · 物理学 2012-04-25 Samira Hamimeche , Antony Lewis

It is possible to classify pixels of a smoothed cosmic microwave background (CMB) fluctuation map according to their local curvature in ``hill'', ``lake'' and ``saddle'' regions. In the Gaussian case, fractional areas occupied by pixels of…

天体物理学 · 物理学 2011-05-10 O. Doré , S. Colombi , F. R. Bouchet

CMB mapmaking relies on a data model to solve for the sky map, and this process is vulnerable to bias if the data model cannot capture the full behavior of the signal. We demonstrate that this bias is not just limited to small-scale effects…

天体物理仪器与方法 · 物理学 2024-08-30 Sigurd Naess , Thibaut Louis

It has been argued recently by Copi etal (2009) that the lack of large angular correlations of the CMB temperature field provides strong evidence against the standard, statistically isotropic, inflationary LambdaCDM cosmology. We compare…

宇宙学与河外天体物理 · 物理学 2015-05-14 George Efstathiou , Yin-Zhe Ma , Duncan Hanson

We perform an analysis of the CMB temperature data taken by the Planck satellite investigating if there is any significant deviation from cosmological isotropy. We look for differences in the spectrum between two opposite hemispheres and…

宇宙学与河外天体物理 · 物理学 2015-01-14 Miguel Quartin , Alessio Notari

We report an improved technique for diffuse foreground minimization from Cosmic Microwave Background (CMB) maps using a new multi-phase iterative internal-linear-combination (ILC) approach in harmonic space. The new procedure consists of…

宇宙学与河外天体物理 · 物理学 2017-09-18 Vipin Sudevan , Pavan K. Aluri , Sarvesh Kumar Yadav , Rajib Saha , Tarun Souradeep

Gaussianity of temperature fluctuations in the Cosmic Microwave Background(CMB) implies that the statistical properties of the temperature field can be completely characterized by its two point correlation function. The two point…

宇宙学与河外天体物理 · 物理学 2013-09-25 Nidhi Joshi , Aditya Rotti , Tarun Souradeep

In this article we present and study a scaling law of the $m\Gamma_m$ CMB Fourier spectrum on rings which allows us (i) to combine spectra corresponding to different colatitude angles (e.g. several detectors at the focal plane of a…

In this talk I propose the first fast methods which can analyze CMB data taking into account correlated noise, arbitrary beam shapes, non-uniform distribution of integration time on the sky, and partial sky coverage, without the need for…

天体物理学 · 物理学 2007-05-23 Benjamin D. Wandelt

We extend the pure pseudo-power-spectrum formalism proposed recently in the context of the Cosmic Microwave Background polarized power spectra estimation by Smith (2006) to incorporate cross-spectra computed for multiple maps of the same…

宇宙学与河外天体物理 · 物理学 2009-07-09 J. Grain , M. Tristram , R. Stompor

We present an application of the fast Independent Component Analysis (FastICA) to the WMAP 3yr data with the goal of extracting the CMB signal. We evaluate the confidence of our results by means of Monte Carlo simulations including CMB,…

天体物理学 · 物理学 2013-01-15 D. Maino , S. Donzelli , A. J. Banday , F. Stivoli , C. Baccigalupi

A new analysis is presented of the angular correlation function $C(\Theta)$ of cosmic microwave background (CMB) temperature at large angular separation, based on published maps derived from {\sl WMAP} and {\sl Planck} satellite data, using…

宇宙学与河外天体物理 · 物理学 2020-01-29 Ray Hagimoto , Craig Hogan , Collin Lewin , Stephan S. Meyer

A fast algorithm is developed for the directional correlation of scalar band-limited signals and band-limited steerable filters on the sphere. The asymptotic complexity associated to it through simple quadrature is of order O(L^5), where 2L…

天体物理学 · 物理学 2011-02-11 Y. Wiaux , L. Jacques , P. Vielva , P. Vandergheynst