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Related papers: A search for concentric circles in the 7-year WMAP…

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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…

Cosmology and Nongalactic Astrophysics · Physics 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

We present limits to the amplitude of non-Gaussian primordial fluctuations in the WMAP 1-year cosmic microwave background sky maps. A non-linear coupling parameter, f_NL, characterizes the amplitude of a quadratic term in the primordial…

We revisit the claimed detection of a new cosmic microwave background (CMB) foreground based on the correlation between low-redshift 2MASS Redshift Survey (2MRS) galaxies and CMB temperature maps from the Planck and WMAP missions. We…

Cosmology and Nongalactic Astrophysics · Physics 2024-07-03 Graeme E. Addison

Recovering the Cosmic Microwave Background (CMB) from WMAP data requires galactic foreground emissions to be accurately separated out. Most component separation techniques rely on second order statistics such as Internal Linear Combination…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-15 J. Bobin , F. Sureau , P. Paykari , A. Rassat , S. Basak , J. -L. Starck

Numerical simulations predict a considerable fraction of the missing baryons at redshift z ~ 0 resting in the so called warm-hot intergalactic medium (WHIM). The filaments and sheets of the WHIM have high temperatures 10^5 - 10^7 K) and a…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 J. S. Klar , J. P. Mücket

We study the statistical properties of spherical harmonic modes of temperature maps of the cosmic microwave background. Unlike other studies, which focus mainly on properties of the amplitudes of these modes, we look instead at their…

Astrophysics · Physics 2009-11-10 Peter Coles , Patrick Dineen , John Earl , Dean Wright

The recent WMAP data represents a milestone in cosmology and helps constrain cosmological parameters with unprecedented accuracy. In this work we combine the WMAP data with previous CMB anisotropy measurements at smaller angular scales to…

Astrophysics · Physics 2015-06-24 C. J. Odman

The claim by Gurzadyan et al. that the cosmological sky is a weakly random one where "the random perturbation is a minor component of mostly regular signal" has given rise to a series of useful exchanges. The possibility that the Cosmic…

General Physics · Physics 2011-10-31 Luis Gonzalez-Mestres

We present local extrema studies of two models that introduce a preferred direction into the observed cosmic microwave background (CMB) temperature field. In particular, we make a frequentist comparison of the one- and two-point statistics…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 Zhen Hou , A. J. Banday , K. M. Gorski , N. E. Groeneboom , H. K. Eriksen

Recent observations revealed loop-like structures at very small scales visible in observables that sample transition region (TR) and coronal temperatures. Their formation remains unclear. We study an example of a bipolar system in realistic…

Solar and Stellar Astrophysics · Physics 2023-03-29 M. Skan , S. Danilovic , J. Leenaarts , F. Calvo , M. Rempel

A remarkable similarity between the large-scale non-Gaussian pattern of cosmic microwave background (CMB) temperatures obtained by Wilkinson Microwave Anisotropy Probe (WMAP) mission and the distribution feature of observation numbers is…

Cosmology and Nongalactic Astrophysics · Physics 2009-09-01 Ti-Pei Li , Hao Liu , Li-Ming Song , Shao-Lin Xiong , Jian-Yin Nie

I discuss whether the standard cosmological models fit the WMAP data well enough to justify parameter estimation with standard assumptions. The observed quadrupole is low (but has significant foreground uncertainty) and drives weak evidence…

Astrophysics · Physics 2017-08-23 Antony Lewis

It has been suggested by Roukema and coworkers (hereafter R04) that the topology of the Universe as probed by the ``matched circles'' method using the first year release of the WMAP CMB data, might be that of the Poincar\'e dodecahedral…

Astrophysics · Physics 2008-04-24 B. S. Lew , B. F. Roukema

The CMB has distinct peaks in both its temperature angular power spectrum (TT) and temperature-polarization cross-power spectrum (TE). From the WMAP data we find the first peak in the temperature spectrum at l = 220.1 +- 0.8 with an…

A number of well-motivated extensions of the LCDM concordance cosmological model postulate the existence of a population of sources embedded in the cosmic microwave background (CMB). One such example is the signature of cosmic bubble…

Cosmology and Nongalactic Astrophysics · Physics 2012-05-29 J. D. McEwen , S. M. Feeney , M. C. Johnson , H. V. Peiris

The first year data from the Wilkinson Microwave Anisotropy Probe are used to place stringent constraints on the topology of the Universe. We search for pairs of circles on the sky with similar temperature patterns along each circle. We…

Astrophysics · Physics 2009-11-10 Neil J. Cornish , David N. Spergel , Glenn D. Starkman , Eiichiro Komatsu

The statistical properties of the temperature anisotropies and polarization of the of cosmic microwave background (CMB) radiation offer a powerful probe of the physics of the early universe. In recent works a statistical procedure based…

Cosmology and Nongalactic Astrophysics · Physics 2017-03-15 M. J. Reboucas , A. Bernui

We study temporally persistent and spatially extended extreme events of temperature anomalies, i.e. heat waves and cold spells, using large deviation theory. To this end, we consider a simplified yet Earth-like general circulation model of…

Statistical Mechanics · Physics 2019-05-22 Vera Melinda Galfi , Valerio Lucarini , Jeroen Wouters

The Wilkinson Microwave Anisotropy Probe (WMAP) has mapped the full sky in Stokes I, Q, and U parameters at frequencies 23, 33, 41, 61, and 94 GHz. We detect correlations between the temperature and polarization maps significant at more…

Astrophysics · Physics 2015-06-24 A. Kogut

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…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-30 D. Larson , J. L. Weiland , G. Hinshaw , C. L. Bennett