English
Related papers

Related papers: Primordial non-Gaussianity estimator: the inhomoge…

200 papers

We estimate the magnitude of the bias due to non-Gaussian extragalactic foregrounds on the optimal reconstruction of the cosmic microwave background (CMB) lensing potential and temperature power spectra. The reconstruction is performed…

Cosmology and Nongalactic Astrophysics · Physics 2025-07-25 M. Doohan , M. Millea , S. Raghunathan , F. Ge , L. Knox , K. Prabhu , C. L. Reichardt , W. L. K. Wu

We investigate an estimator to measure the primordial trispectrum in equilateral type non-Gaussian models such as k-inflation, single field DBI inflation and multi-field DBI inflation models from Cosmic Microwave Background (CMB)…

High Energy Physics - Theory · Physics 2014-11-21 Shuntaro Mizuno , Kazuya Koyama

Cross-correlations between Cosmic Microwave Background (CMB) temperature and $y$-spectral distortions anisotropies have been previously proposed as a way to measure the local bispectrum parameter $f_{\rm NL}^{\rm loc.}$ in a range of scales…

Cosmology and Nongalactic Astrophysics · Physics 2017-10-04 Andrea Ravenni , Michele Liguori , Nicola Bartolo , Maresuke Shiraishi

We present an upgraded combined estimator, based on Minkowski Functionals and Neural Networks, with excellent performance in detecting primordial non-Gaussianity in simulated maps that also contain a weighted mixture of Galactic…

Cosmology and Nongalactic Astrophysics · Physics 2015-10-07 C. P. Novaes , A. Bernui , I. S. Ferreira , C. A. Wuensche

A very important property of a statistical distribution is to know whether it obeys Gaussian statistics or not. On the one hand, it is of paramount importance in the context of CMB anisotropy studies, since deviations from a Gaussian…

Astrophysics · Physics 2009-10-31 N. Aghanim , O. Forni , F. R. Bouchet

The quality of CMB observations has improved dramatically in the last few years, and will continue to do so in the coming decade. Over a wide range of angular scales, the uncertainty due to instrumental noise is now small compared to the…

We investigate the relative sensitivities of several tests for deviations from Gaussianity in the primordial distribution of density perturbations. We consider models for non-Gaussianity that mimic that which comes from inflation as well as…

Astrophysics · Physics 2009-10-31 Licia Verde , Raul Jimenez , Marc Kamionkowski , Sabino Matarrese

Our view of the last-scattering surface in the cosmic microwave background (CMB) is obscured by secondary anisotropies, sourced by scattering, extragalactic emission and gravitational processes between recombination and observation. Whilst…

Cosmology and Nongalactic Astrophysics · Physics 2023-05-10 William Coulton , Alexander Miranthis , Anthony Challinor

All the analyses of Cosmic Microwave Background (CMB) temperature maps up--to--date show that CMB anisotropies follow a Gaussian distribution. On the other hand, astrophysical foregrounds which hamper the detection of the CMB angular power…

Astrophysics · Physics 2008-11-26 F. Argüeso , J. González-Nuevo , L. Toffolatti

Primordial magnetic fields present since before the epoch of matter-radiation equality have an effect on the anisotropies of the cosmic microwave background. The CMB anisotropies due to scalar perturbations are calculated in the gauge…

Cosmology and Nongalactic Astrophysics · Physics 2011-02-02 Kerstin E. Kunze

The peculiar motion of an observer with respect to the CMB rest frame induces a deflection in the arrival direction of the observed photons (also known as CMB aberration) and a Doppler shift in the measured photon frequencies. As a…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 Riccardo Catena , Michele Liguori , Alessio Notari , Alessandro Renzi

A future detection of the Stochastic Gravitational Wave Background (SGWB) with GW experiments is expected to open a new window on early universe cosmology and on the astrophysics of compact objects. In this paper we study SGWB anisotropies,…

Cosmology and Nongalactic Astrophysics · Physics 2020-07-22 N. Bartolo , D. Bertacca , S. Matarrese , M. Peloso , A. Ricciardone , A. Riotto , G. Tasinato

Gaussianity is the very base for derivation of the cosmological parameters from the CMB angular power spectrum. Non-Gaussian signal, whether originated from experimental error or primordial source, could mimic extra power in the power…

Astrophysics · Physics 2009-11-11 Pavel Naselsky , Lung-Yih Chiang , Poul Olesen , Igor Novikov

The Planck CMB experiment has delivered the best constraints so far on primordial non-Gaussianity, ruling out early-Universe models of inflation that generate large non-Gaussianity. Although small improvements in the CMB constraints are…

In the recent years, non-Gaussianity and statistical isotropy of the Cosmic Microwave Background (CMB) was investigated with various statistical measures, first and foremost by means of the measurements of the WMAP satellite. In this…

Cosmology and Nongalactic Astrophysics · Physics 2011-10-21 G. Rossmanith , H. Modest , C. Raeth , A. J. Banday , K. M. Gorski , G. Morfill

We describe a Bayesian framework for estimating the time-domain noise covariance of CMB observations, typically parametrized in terms of a 1/f frequency profile. This framework is based on the Gibbs sampling algorithm, which allows for…

Instrumentation and Methods for Astrophysics · Physics 2015-05-30 I. K. Wehus , S. K. Næss , H. K. Eriksen

Strong foreground contamination in high resolution CMB data requires masking which introduces statistical anisotropies and renders a full maximum likelihood analysis numerically intractable. Standard analysis methods like the pseudo-C_l…

Cosmology and Nongalactic Astrophysics · Physics 2014-03-26 H. F. Gruetjen , E. P. S. Shellard

While usually cosmological initial conditions are assumed to be Gaussian, inflationary theories can predict a certain amount of primordial non-Gaussianity which can have an impact on the statistical properties of the lensing observables. In…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-17 F. Pace , L. Moscardini , M. Bartelmann , E. Branchini , K. Dolag , M. Grossi , S. Matarrese

Gaussianity and statistical isotropy of the Universe are modern cosmology's minimal set of hypotheses. In this work we introduce a new statistical test to detect observational deviations from this minimal set. By defining the temperature…

Cosmology and Nongalactic Astrophysics · Physics 2009-09-30 Thiago S. Pereira , L. Raul Abramo

We present a new method based on the N-point probability distribution (pdf) to study non-Gaussianity in cosmic microwave background (CMB) maps. Likelihood and Bayesian estimation are applied to a local non-linear perturbed model up to third…

Astrophysics · Physics 2015-05-13 P. Vielva , J. L. Sanz