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相关论文: Astro-ph communication: Simulations of the WMAP In…

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We examine the consistency of WMAP9 and Planck data. We compare sky maps, power spectra, and inferred LCDM cosmological parameters. Residual dipoles are seen in the WMAP and Planck sky map differences, but are consistent within the…

宇宙学与河外天体物理 · 物理学 2015-03-30 D. Larson , J. L. Weiland , G. Hinshaw , C. L. Bennett

We revisit the alignments of the largest structures observed in the cosmic microwave background (CMB) using the seven and nine-year WMAP and first-year Planck data releases. The observed alignments -- the quadrupole with the octopole and…

宇宙学与河外天体物理 · 物理学 2015-06-04 Craig J. Copi , Dragan Huterer , Dominik J. Schwarz , Glenn D. Starkman

The `Internal Linear Combination' (ILC) component separation method has been extensively used on the data of the WMAP space mission, to extract a single component, the CMB, from the WMAP multifrequency data. We extend the ILC approach for…

宇宙学与河外天体物理 · 物理学 2015-05-19 Mathieu Remazeilles , Jacques Delabrouille , Jean-Francois Cardoso

ABRIDGED: We introduce and analyze a method for testing statistical isotropy and Gaussianity and apply it to the WMAP CMB foreground reduced, temperature maps, and cross-channel difference maps. We divide the sky into regions of varying…

天体物理学 · 物理学 2009-06-23 Bartosz Lew

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)…

天体物理学 · 物理学 2009-11-10 P. Bielewicz , K. M. Gorski , A. J. Banday

Statistical isotropy (SI) has been one of the simplifying assumptions in cosmological model building. Experiments like WMAP and PLANCK are attempting to test this assumption by searching for specific signals in the Cosmic Microwave…

宇宙学与河外天体物理 · 物理学 2011-11-21 Aditya Rotti , Moumita Aich , Tarun Souradeep

The first observations of the cosmic microwave background (CMB) from NASA's \emph{Wilkinson Microwave Anisotropy Probe} (WMAP) led to finding `alignment' anomalies not expected from fluctuations in the isotropic cosmological model. We study…

宇宙学与河外天体物理 · 物理学 2025-06-03 Sanjeet Kumar Patel , Pavan Kumar Aluri , John P. Ralston

The coming Planck and Herschel missions will survey the sky at unprecedented angular scales and sensitivities. Simulations are needed for better interpretating the results of the surveys and for testing new methods of, e.g., source…

天体物理学 · 物理学 2009-11-13 N. Fernandez-Conde , G. Lagache , J. -L. Puget , H. Dole

We study the large-scale angular correlation signatures of the Cosmic Microwave Background (CMB) temperature fluctuations from WMAP data in several spherical cap regions of the celestial sphere, outside the Kp0 or Kp2 cut-sky masks. We…

天体物理学 · 物理学 2008-11-26 Armando Bernui , Thyrso Villela , Carlos A. Wuensche , Rodrigo Leonardi , Ivan Ferreira

Several analyses of the microwave sky maps from the Wilkinson Microwave Anisotropy Probe (WMAP) have drawn attention to alignments amongst the low-order multipoles. Amongst the various possible explanations, an effect of cosmic topology has…

天体物理学 · 物理学 2009-11-13 James G. Cresswell , Andrew R. Liddle , Pia Mukherjee , Alain Riazuelo

We propose two detection techniques that take advantage of a small sky area approximation and are based on modifications of the "internal linear combination" (ILC) method, an approach widely used in Cosmology for the separation of the…

天体物理仪器与方法 · 物理学 2012-06-21 R. Vio , P. Andreani , E. P. R. G. Ramos , A. da Silva

We have derived whole-sky CMB polarization maps from the WMAP 5 year polarization data, using the Harmonic Internal Linear Combination (HILC) method. Our HILC method incorporates spatial variability of linear weights in a natural way and…

天体物理学 · 物理学 2009-04-06 Jaiseung Kim , Pavel Naselsky , Per Rex Christensen

Using a set of compilations of measurements for extragalactic radio sources we construct all-sky maps of the Faraday Rotation produced by the Galactic magnetic field. In order to generate the maps we treat the radio source positions as a…

天体物理学 · 物理学 2009-11-10 Patrick Dineen , Peter Coles

The method of correlation mapping on the full sphere is used to study the properties of the ILC map, as well as the dust and synchrotron background components. An anomalous correlation of the components with the ILC map in the main plane…

宇宙学与河外天体物理 · 物理学 2011-08-23 O. V. Verkhodanov , M. L. Khabibullina

Recently a symmetry-based method to test for statistical isotropy of the cosmic microwave background was developed. We apply the method to template-cleaned 3-year and 5-year WMAP-$DA$ maps. We examine a wide range of angular multipoles from…

天体物理学 · 物理学 2010-11-02 Pramoda Kumar Samal , Rajib Saha , Pankaj Jain , John P. Ralston

In order to test for non-Gaussianities with respect to scale-dependencies we use so-called surrogate maps, in which possible phase correlations of the Fourier phases of the original WMAP data and simulations, respectively, are destroyed by…

宇宙学与河外天体物理 · 物理学 2015-06-11 H. I. Modest , C. Räth , A. J. Banday , G. Rossmanith , R. Sütterlin , S. Basak , J. Delabrouille , K. M. Górski , G. E. Morfill

In this article we propose a novel test for statistical anisotropy of the CMB. The test is based on the fact, that the Galactic foregrounds have a remarcably strong symmetry with respect to their antipodal points and with respect to the…

宇宙学与河外天体物理 · 物理学 2015-05-28 P. Naselsky , M. Hansen , J. Kim

Recent analyses of the WMAP data seem to indicate the possible presence of large-angle anisotropy in the Universe. If confirmed, these can have important consequences for our understanding of the Universe. A number of attempts have recently…

天体物理学 · 物理学 2009-06-23 A. Bernui , B. Mota , M. J. Reboucas , R. Tavakol

In this work, we formalize a new technique to investigate joint posterior density of Cosmic Microwave Background (CMB) signal and its theoretical angular power spectrum given the observed data, using the global internal-linear-combination…

宇宙学与河外天体物理 · 物理学 2018-10-23 Vipin Sudevan , Rajib Saha

We show that the popular ILC approach is unstable in respect to the division of the sample of map pixels to the set of ``homogeneous'' subsamples. For suitable choice of such subsamples we can obtain the restored CMB signal with amplitudes…

宇宙学与河外天体物理 · 物理学 2011-02-18 A. Doroshkevich , O. Verkhodanov