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Related papers: Primordial non-Gaussian signatures in CMB polariza…

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In this paper we demonstrate an efficient method for including both CMB temperature and polarisation data in optimal non-Gaussian estimators. The method relies on orthogonalising the multipoles of the temperature and polarisation maps and…

Cosmology and Nongalactic Astrophysics · Physics 2014-09-05 J. R. Fergusson

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

In the context of the present and future Cosmic Microwave Background (CMB) experiments, going beyond the information provided by the power spectrum has become necessary in order to tightly constrain the cosmological model. The non-Gaussian…

Astrophysics · Physics 2008-11-26 N. Aghanim , M. Kunz , P. G. Castro , O. Forni

The subject of this paper is the investigation of inflationary non-Gaussianities of the local type with extreme value statistics of the weak lensing convergence kappa. Specifically, we describe the influence of inflationary…

Cosmology and Nongalactic Astrophysics · Physics 2013-05-08 Federica Capranico , Angelos Fotios Kalovidouris , Bjoern Malte Schaefer

Primordial magnetic fields (PMF) can create polarization $B$-modes in the cosmic microwave background (CMB) through Faraday rotation (FR), leading to non-trivial 2-point and 4-point correlators of the CMB temperature and polarization. We…

Cosmology and Nongalactic Astrophysics · Physics 2013-05-30 Amit P. S. Yadav , Levon Pogosian , Tanmay Vachaspati

Local non-Gaussianity causes correlations between large scale perturbation modes and the small scale power. The large-scale CMB signal has contributions from the integrated Sachs Wolfe (ISW) effect, which does not correlate with the small…

Cosmology and Nongalactic Astrophysics · Physics 2011-02-02 James M. G. Mead , Antony Lewis , Lindsay J. King

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 derive a general expression for the probability of observing deviations from statistical isotropy in the cosmic microwave background (CMB) if the primordial fluctuations are non-Gaussian and extend to superhorizon scales. The primary…

Cosmology and Nongalactic Astrophysics · Physics 2016-01-27 Saroj Adhikari , Sarah Shandera , Adrienne L. Erickcek

We study primordial non-Gaussian signatures in the redshift-space halo field on non-linear scales, using a quasi-maximum likelihood estimator based on optimally compressed power spectrum and modal bispectrum statistics. We train and…

The B modes generated by the lensing of CMB polarization are a primary target for the upcoming generation of experiments and can potentially constrain quantities such as the neutrino mass and dark energy equation of state. The net sample…

Astrophysics · Physics 2011-05-12 Kendrick M. Smith , Wayne Hu , Manoj Kaplinghat

Primordial magnetic fields lead to non-Gaussian signals in the cosmic microwave background (CMB) even at the lowest order, as magnetic stresses and the temperature anisotropy they induce depend quadratically on the magnetic field. In…

Cosmology and Nongalactic Astrophysics · Physics 2011-01-17 Pranjal Trivedi , Kandaswamy Subramanian , T. R. Seshadri

We present a set of formalisms for comparing, evolving and constraining primordial non-Gaussian models through the CMB bispectrum. We describe improved methods for efficient computation of the full CMB bispectrum for any general…

Astrophysics · Physics 2009-09-02 J. R. Fergusson , E. P. S. Shellard

The 21-cm brightness temperature fluctuation from the Dark Ages ($z \simeq 30-100$) will allow us to probe the inflationary epoch on very small scales ($>0.1 \, \mbox{Mpc}^{-1}$), inaccessible to cosmic microwave background experiments.…

Cosmology and Nongalactic Astrophysics · Physics 2023-07-28 Giorgio Orlando , Thomas Flöss , P. Daniel Meerburg , Joseph Silk

We test the statistical isotropy (SI) of the $E$-mode polarization of the cosmic microwave background (CMB) radiation observed by the Planck satellite using two statistics, namely, the contour Minkowski Tensor (CMT) and the Directional…

Cosmology and Nongalactic Astrophysics · Physics 2020-06-29 Joby P. Kochappan , Aparajita Sen , Tuhin Ghosh , Pravabati Chingangbam , Soumen Basak

We study CMB constraints on non-Gaussianity from isocurvature perturbations of general types. Specifically, we study CDM/neutrino isocurvature perturbations which are uncorrelated or totally correlated with adiabatic ones. Using the data…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 Chiaki Hikage , Masahiro Kawasaki , Toyokazu Sekiguchi , Tomo Takahashi

The primordial non-Gaussianity induces scale-dependent bias of the \hi with respect to the underlying dark matter, which exhibits features on the very large scales of the 21-cm power spectrum potentially observable with \hi intensity…

Cosmology and Nongalactic Astrophysics · Physics 2017-10-04 Yi-Chao Li , Yin-Zhe Ma

We apply the time-renormalization group approach to study the effect of primordial non-Gaussianities in the non-linear evolution of cosmological dark matter density perturbations. This method improves the standard perturbation approach by…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 Nicola Bartolo , J. P. Beltran Almeida , Sabino Matarrese , Massimo Pietroni , Antonio Riotto

We investigate optimization strategies to measure primordial non-Gaussianity with future spectroscopic surveys. We forecast measurements coming from the 3D galaxy power spectrum and compute constraints on primordial non-Gaussianity…

Cosmology and Nongalactic Astrophysics · Physics 2015-08-26 Alvise Raccanelli , Olivier Dore , Neal Dalal

We present a method to simulate the polarization properties of extragalactic radio sources at microwave frequencies. Polarization measurements of nearly 2x10^6 sources at 1.4 GHz are provided by the NVSS survey. Using this catalogue and the…

Astrophysics · Physics 2008-11-26 M. Tucci , E. Martinez-Gonzalez , L. Toffolatti , J. Gonzalez-Nuevo , G. De Zotti

In this paper we propose a new statistic capable of detecting non-Gaussianity in the CMB. The statistic is defined in Fourier space, and therefore naturally separates angular scales. It consists of taking another Fourier transform, in…

Astrophysics · Physics 2010-04-08 Alex Lewin , Andreas Albrecht , Joao Magueijo
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