English
Related papers

Related papers: Scale-dependent non-Gaussianities in the WMAP data…

200 papers

We demonstrate the feasibility to generate surrogates by Fourier-based methods for an incomplete data set. This is performed for the case of a CMB analysis, where astrophysical foreground emission, mainly present in the Galactic plane, is a…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-05 G. Rossmanith , H. Modest , C. Räth , A. J. Banday , K. M. Gorski , G. Morfill

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

[Abridged] We consider how galaxy clustering data, from Mpc to Gpc scales, from upcoming large scale structure surveys, such as Euclid and DESI, can provide discriminating information about the bispectrum shape arising from a variety of…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-22 Joyce Byun , Rachel Bean

In these lecture notes I discussed the importance of phase correlations for the morphology of large-scale structure and how phase analysis can probe primordial non-Gaussianity and/or foreground contamination in CMB temperature maps. I…

Astrophysics · Physics 2007-05-23 Peter Coles

Despite the wealth of $Planck$ results, there are difficulties in disentangling the primordial non-Gaussianity of the Cosmic Microwave Background (CMB) from the secondary and the foreground non-Gaussianity (NG). For each of these forms of…

Cosmology and Nongalactic Astrophysics · Physics 2017-04-10 Thomas Buchert , Martin J. France , Frank Steiner

We forecast combined future constraints from the cosmic microwave background and large-scale structure on the models of primordial non-Gaussianity. We study the generalized local model of non-Gaussianity, where the parameter f_NL is…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-05 Adam Becker , Dragan Huterer , Kenji Kadota

We consider cosmological inflationary models in which vector fields play some role in the generation of the primordial curvature perturbation $\zeta$. Such models are interesting because the involved vector fields naturally seed statistical…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-19 Juan P. Beltran Almeida , Yeinzon Rodriguez , Cesar A. Valenzuela-Toledo

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…

We generalize the concept of the ordinary skew-spectrum to probe the effect of non-Gaussianity on the morphology of Cosmic Microwave Background (CMB) maps in several domains: in real-space (where they are commonly known as…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 Dipak Munshi , Joseph Smidt , Asantha Cooray , Alessandro Renzi , Alan Heavens , Peter Coles

Many inflation models predict that primordial density perturbations have a nonzero three-point correlation function, or bispectrum in Fourier space. Of the several possibilities for this bispectrum, the most commmon is the local-model…

Cosmology and Nongalactic Astrophysics · Physics 2015-07-01 Razieh Emami , Emanuela Dimastrogiovanni , Jens Chluba , Marc Kamionkowski

Recent progress has revealed a number of constraints that cosmological correlators and the closely related field-theoretic wavefunction must obey as a consequence of unitarity, locality, causality and the choice of initial state. When…

High Energy Physics - Theory · Physics 2024-03-20 Carlos Duaso Pueyo , Enrico Pajer

We repeat the directional spherical real Morlet wavelet analysis used to detect non-Gaussianity in the WMAP 1-year data (McEwen et al. 2005a), on the WMAP 3-year data. The non-Gaussian signal previously detected is indeed present in the…

Astrophysics · Physics 2011-02-11 J. D. McEwen , M. P. Hobson , A. N. Lasenby , D. J. Mortlock

The normalisation of the matter power spectrum, sigma_8, is an essential ingredient to predict the phenomenology of the low redshift universe. It has been measured using several methods, such as X-ray cluster counts, weak lensing and the…

Astrophysics · Physics 2008-11-26 A. Amara , A. Refregier

We present a Gaussianity analysis of the WMAP 5-year Cosmic Microwave Background (CMB) temperature anisotropy data maps. We use several third order estimators based on the spherical Mexican hat wavelet. We impose constraints on the local…

We forecast constraints on primordial non-Gaussianity achievable from forthcoming surveys by exploiting the scale-dependent halo bias introduced on large scales by non-Gaussian initial conditions. We explore the performance of exploiting…

Astrophysics · Physics 2010-03-26 Carmelita Carbone , Licia Verde , Sabino Matarrese

We use Minkowski Functionals to explore the presence of non-Gaussian signatures in simulated cosmic microwave background (CMB) maps. Precisely, we analyse the non-Gaussianities produced from the angular power spectra emerging from a class…

Cosmology and Nongalactic Astrophysics · Physics 2023-03-08 Camila P. Novaes , Micol Benetti , Armando Bernui

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

A highly non-gaussian cosmological perturbation with a flat spectrum has unusual stochastic properties. We show that they depend on the size of the box within which the perturbation is defined, but that for a typical observer the parameters…

Astrophysics · Physics 2011-05-05 Lotfi Boubekeur , David. H. Lyth

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…

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…

Astrophysics · Physics 2011-05-10 O. Doré , S. Colombi , F. R. Bouchet