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We analyse the large-scale angular clustering of quasars in the \gaia-\unwise quasar catalog, \quaia, and their cross-correlation with maps of the lensing convergence of the Cosmic Microwave Background (CMB), to constrain the level of…

Cosmology and Nongalactic Astrophysics · Physics 2026-05-19 Giulio Fabbian , David Alonso , Kate Storey-Fisher , Thomas Cornish

We develop a needlet approach to estimate the amplitude of general (including non-separable) bispectra and trispectra in the cosmic microwave background, and apply this to the WMAP 9-year data. We obtain estimates for the `orthogonal'…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-17 Donough Regan , Mateja Gosenca , David Seery

We introduce an exact Bayesian approach to search for non-Gaussianity of local type in Cosmic Microwave Background (CMB) radiation data. Using simulated CMB temperature maps, the newly developed technique is compared against the…

Cosmology and Nongalactic Astrophysics · Physics 2010-11-15 Franz Elsner , Benjamin D. Wandelt

We search for planar deviations of statistical isotropy in the Wilkinson Microwave Anisotropy Probe (WMAP) data by applying a recently introduced angular-planar statistics both to full-sky and to masked temperature maps, including in our…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 L. Raul Abramo , Armando Bernui , Thiago S. Pereira

We study the Likelihood function of data given f_NL for the so-called local type of non-Gaussianity. In this case the curvature perturbation is a non-linear function, local in real space, of a Gaussian random field. We compute the…

Astrophysics · Physics 2010-10-27 Paolo Creminelli , Leonardo Senatore , Matias Zaldarriaga

Several inflationary models predict the possibility that the primordial perturbations of the density field may contain a degree of non-Gaussianity which would influence the subsequent evolution of cosmic structures at large scales. In order…

Cosmology and Nongalactic Astrophysics · Physics 2011-04-07 M. Roncarelli , L. Moscardini , E. Branchini , K. Dolag , M. Grossi , F. Iannuzzi , S. Matarrese

A directional spherical wavelet analysis is performed to examine the Gaussianity of the WMAP 1-year data. Such an analysis is facilitated by the introduction of a fast directional continuous spherical wavelet transform. The directional…

Astrophysics · Physics 2008-03-04 J. D. McEwen , M. P. Hobson , A. N. Lasenby , D. J. Mortlock

We present an approximate calculation of the full Bayesian posterior probability distribution for the local non-Gaussianity parameter $f_{\text{nl}}$ from observations of cosmic microwave background anisotropies within the framework of…

Cosmology and Nongalactic Astrophysics · Physics 2013-11-14 Sebastian Dorn , Niels Oppermann , Rishi Khatri , Marco Selig , Torsten A. Enßlin

Wide-angle and relativistic corrections to the Newtonian and flat-sky approximations are important for accurate modeling of the galaxy power spectrum of next-generation galaxy surveys. In addition to Doppler and Sachs-Wolfe relativistic…

Cosmology and Nongalactic Astrophysics · Physics 2025-07-24 Sêcloka L. Guedezounme , Sheean Jolicoeur , Roy Maartens

Measurements of primordial non-Gaussianity ($f_{NL}$) open a new window onto the physics of inflation. We describe a fast cubic (bispectrum) estimator of $f_{NL}$, using a combined analysis of temperature and polarization observations. The…

Astrophysics · Physics 2009-02-23 Amit P. S. Yadav , Eiichiro Komatsu , Benjamin D. Wandelt

Aims: We outline the Bayesian approach to inferring f_NL, the level of non-Gaussianity of local type. Phrasing f_NL inference in a Bayesian framework takes advantage of existing techniques to account for instrumental effects and foreground…

Cosmology and Nongalactic Astrophysics · Physics 2010-11-23 Franz Elsner , Benjamin D. Wandelt , Michael D. Schneider

A measurement of primordial non-gaussianity will be of paramount importance to distinguish between different models of inflation. Cosmic microwave background (CMB) anisotropy observations have set unprecedented bounds on the non-gaussianity…

Cosmology and Nongalactic Astrophysics · Physics 2015-10-14 Julian B. Muñoz , Yacine Ali-Haïmoud , Marc Kamionkowski

We use hydrodynamical separate universe simulations with the IllustrisTNG model to predict the local primordial non-Gaussianity (PNG) bias parameters $b_{\phi}$ and $b_{\phi\delta}$, which enter at leading order in the galaxy power spectrum…

Cosmology and Nongalactic Astrophysics · Physics 2022-01-21 Alexandre Barreira

We consider how measurements of the 21cm radiation from the epoch of reionization (z=8-12) can constrain the amplitudes of various `shapes' of primordial non-Gaussianity. The limits on these shapes, each parametrized by the non-linear…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-15 Sirichai Chongchitnan

[Abridged] In this paper we explore a local non-linear perturbative model up to third order as a general characterization of the CMB anisotropies. We focus our analysis in large scale anisotropies. At these angular scales, the non-Gaussian…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-14 P. Vielva , J. L. Sanz

We study perturbations in the multi-field axion Nflation model, taking account of the full cosine potential. We find significant differences with previous analyses which made a quadratic approximation to the potential. The tensor-to-scalar…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-17 Soo A Kim , Andrew R Liddle , David Seery

We apply a previously developed Gibbs sampling framework to the foreground corrected 3-yr WMAP polarization data and compute the power spectrum and residual foreground template amplitude posterior distributions. We first analyze the…

We present constraints on $f_{\rm NL}$, the parameter quantifying the amplitude of local Primordial Non-Gaussianities (PNG), from a combined analysis of the tree-level power spectrum and bispectrum of Data Release $16$ (DR16) of the…

Cosmology and Nongalactic Astrophysics · Physics 2025-07-21 Marina S. Cagliari , Matilde Barberi-Squarotti , Kevin Pardede , Emanuele Castorina , Guido D'Amico

Local primordial non-Gaussianity (PNG) is a promising observable of the underlying physics of inflation, characterised by $f_{\rm NL}^{\rm loc}$. We present the methodology to measure $f_{\rm NL}^{\rm loc}$ from the Dark Energy Survey (DES)…

One of the principle efforts in cosmic microwave background (CMB) research is measurement of the parameter fnl that quantifies the departure from Gaussianity in a large class of non-minimal inflationary (and other) models. Estimators for…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 Tristan L. Smith , Marc Kamionkowski , Benjamin D. Wandelt