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We approximately compute the bispectrum induced on the CMB temperature by fluctuations in the standard recombination epoch. Of all the second order sources that can induce non-Gaussianity during recombination, we concentrate on those…

Astrophysics · Physics 2009-10-02 Leonardo Senatore , Svetlin Tassev , Matias Zaldarriaga

Full sky maps are made in five microwave frequency bands to separate the temperature anisotropy of the CMB from foreground emission. We define masks that excise regions of high foreground emission. The effectiveness of template fits to…

The identification of non-Gaussian signatures in cosmic microwave background (CMB) temperature maps is one of the main cosmological challenges today. We propose and investigate altenative methods to analyse CMB maps. Using the technique of…

Astrophysics · Physics 2009-11-07 C. Raeth , P. Schuecker

Here we review the present status of modelling of and searching for primordial non-Gaussianity of cosmological perturbations. After introducing the models for non-Gaussianity generation during inflation, we discuss the search for…

Cosmology and Nongalactic Astrophysics · Physics 2018-12-21 Marco Celoria , Sabino Matarrese

We propose a method to probe higher-order correlators of the primordial density field through the inhomogeneity of local non-Gaussian parameters, such as f_NL, measured within smaller patches of the sky. Correlators between n-point…

Cosmology and Nongalactic Astrophysics · Physics 2012-09-28 Christian T. Byrnes , Sami Nurmi , Gianmassimo Tasinato , David Wands

We present the strongest robust constraints on primordial non-Gaussianity (PNG) from currently available galaxy surveys, combining large-scale clustering measurements and their cross-correlations with the cosmic microwave background. We…

Cosmology and Nongalactic Astrophysics · Physics 2014-01-22 Tommaso Giannantonio , Ashley J. Ross , Will J. Percival , Robert Crittenden , David Bacher , Martin Kilbinger , Robert Nichol , Jochen Weller

Diffuse Galactic emission at low frequencies is a major contaminant for studies of redshifted $21$ cm line studies. Removal of these foregrounds is essential for exploiting the signal from neutral hydrogen at high redshifts. Analysis of…

Cosmology and Nongalactic Astrophysics · Physics 2018-09-05 Sandeep Rana , Tuhin Ghosh , J. S. Bagla , Pravabati Chingangbam

We studied the effect of primordial non-Gaussianity with varied bispectrum shapes on the number counts of signal-to-noise peaks in wide field cosmic shear maps. The two cosmological contributions to this particular weak lensing statistic,…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 M. Maturi , C. Fedeli , L. Moscardini

This is a review of models of inflation and of their predictions for the primordial non-Gaussianity in the density perturbations which are thought to be at the origin of structures in the Universe. Non-Gaussianity emerges as a key…

Astrophysics · Physics 2009-11-10 N. Bartolo , E. Komatsu , S. Matarrese , A. Riotto

We introduce a general class of models for charaterizing the non-Gaussian properties of foreground contaminants in the cosmic microwave background with view towards the removal of the non-primordial non-Gaussian signal from the primordial…

Cosmology and Nongalactic Astrophysics · Physics 2009-11-05 C. S. Carvalho

We use the full bispectrum of spherical needlets applied to the WMAP data of the cosmic microwave background as an estimator for the primordial non-Gaussianity parameter f_NL. We use needlet scales up to l_max=1000 and the KQ75 galactic cut…

Cosmology and Nongalactic Astrophysics · Physics 2009-08-11 Oystein Rudjord , Frode K. Hansen , Xiaohong Lan , Michele Liguori , Domenico Marinucci , Sabino Matarrese

Using an optimal estimator for the CMB Angular Power Spectrum we compute the temperature two-point correlation function of WMAP 9 year at low resolution. Supported by realistic Monte-Carlo simulations, we evaluate how such observed function…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-17 A. Gruppuso

We present an assessment of the CMB large scale anomalies in polarisation using the two-point correlation function as a test case. We employ the state of the art of large scale polarisation datasets: the first based on a Planck 2018 HFI 100…

Cosmology and Nongalactic Astrophysics · Physics 2021-08-25 Caterina Chiocchetta , Alessandro Gruppuso , Massimiliano Lattanzi , Paolo Natoli , Luca Pagano

If the primordial fluctuations are non-Gaussian, then this non-Gaussianity will be apparent in the cosmic microwave background (CMB) sky. With their sensitive all-sky observation, MAP and Planck satellites should be able to detect weak…

Astrophysics · Physics 2009-07-09 Eiichiro Komatsu , David N. Spergel

We demonstrate an approach that allows separating two-point correlations created by a Gaussian random field from correlations created by cosmic foregrounds such as polarized dust emission, gravitational lensing and other non-Gaussian…

Cosmology and Nongalactic Astrophysics · Physics 2024-11-26 D. I. Novikov , K. O. Parfenov

A previous work (Monteser\'in et al. 2008) estimated the CMB variance from the three-year WMAP data, finding a lower value than expected from Gaussian simulations using the WMAP best-fit cosmological model. We repeat the analysis on the…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 M. Cruz , P. Vielva , E. Martínez-González , R. B. Barreiro

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

Potential evidence for primordial non-Gaussianity (PNG) is expected to lie in the largest scales mapped by cosmological surveys. Forthcoming 21cm intensity mapping experiments will aim to probe these scales by surveying neutral hydrogen…

Cosmology and Nongalactic Astrophysics · Physics 2020-10-20 Steven Cunnington , Stefano Camera , Alkistis Pourtsidou

[Abridged] We present updated estimates of Galactic foreground emission using seven years of WMAP data. Using the power spectrum of differences between multi-frequency template-cleaned maps, we find no evidence for foreground contamination…

Primordial non-Gaussianity is one of the most powerful probes of the inflationary epoch. The particle spectrum relevant to inflation, including masses and spins, is encoded in the precise form of statistical correlations of the adiabatic…

Cosmology and Nongalactic Astrophysics · Physics 2026-04-03 Eugene Chen , Daniel Green , Vincent S. H. Lee
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