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Related papers: Non-Gaussianity from extragalactic point-sources

200 papers

When constraining the primordial non-Gaussianity parameter f_NL with cosmic microwave background anisotropy maps, the bias resulting from the covariance between primordial non-Gaussianity and secondary non-Gaussianities to the estimator of…

Astrophysics · Physics 2008-11-26 Paolo Serra , Asantha Cooray

Galaxy cluster surveys will be a powerful probe of dark energy. At the same time, cluster abundance is sensitive to any non-Gaussianity of the primordial density field. It is therefore possible that non-Gaussian initial conditions might be…

Astrophysics · Physics 2010-11-05 Emiliano Sefusatti , Chris Vale , Kenji Kadota , Joshua Frieman

In this letter we present constraints on the scale-dependent "local" type primordial non-Gaussianity, which is described by non-Gaussianity's spectral index $n_{\rm NG}$, from the NRAO VLA Sky Survey and the quasar catalog of the Sloan…

Cosmology and Nongalactic Astrophysics · Physics 2020-01-08 Ji-Ping Dai , Jun-Qing Xia

We present some first results on the variability, polarization and general properties of radio sources selected in a blind survey at 20 GHz, the highest frequency at which a sensitive radio survey has been carried out over a large area of…

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

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

Our present understanding of the extragalactic source counts and background radiation at infrared and sub-mm wavelengths is reviewed. Available count data are used to constrain evolutionary models of galaxies and Active Nuclei. The CIRB, on…

Non-Gaussian statistics in the distribution of large scale structure, and in temperature fluctuations of the cosmic microwave background, can be used to constrain inflationary models. Data on the cosmic microwave background from Planck…

General Relativity and Quantum Cosmology · Physics 2018-03-06 Nick Woods

We discuss the contribution of the blazar population to the extragalactic background radiation across the electromagnetic (e.m.) spectrum with particular reference to the microwave, hard-X-ray and gamma-ray bands. Our estimates are based on…

Astrophysics · Physics 2007-05-23 P. Giommi , S. Colafrancesco

We present a combined radio/X-ray study of six massive galaxy clusters, aimed at determining the potential for heating of the intra-cluster medium (ICM) by non-central radio galaxies. Since X-ray cavities associated with the radio lobes of…

Cosmology and Nongalactic Astrophysics · Physics 2022-04-27 Ruchika Seth , Ewan O'Sullivan , Biny Sebastian , Somak Raychaudhury , Gerrit Schellenberger , Christopher P. Haines

We present polarisation properties at $1.4\,$GHz of two separate extragalactic source populations: passive quiescent galaxies and luminous quasar-like galaxies. We use data from the {\it Wide-Field Infrared Survey Explorer} data to…

Astrophysics of Galaxies · Physics 2015-06-19 J. K. Banfield , D. H. F. M. Schnitzeler , S. J. George , R. P. Norris , T. H. Jarrett , A. R. Taylor , J. M. Stil

In the pursuit of primordial non-Gaussianities, we hope to access smaller scales across larger comoving volumes. At low redshift, the search for primordial non-Gaussianities is hindered by gravitational collapse, to which we often associate…

Cosmology and Nongalactic Astrophysics · Physics 2023-02-08 Thomas Flöss , Matteo Biagetti , P. Daniel Meerburg

The late-time effect of primordial non-Gaussianity offers a window into the physics of inflation and the very early Universe. In this work we study the consequences of a particular class of primordial non-Gaussianity that is fully…

Cosmology and Nongalactic Astrophysics · Physics 2022-02-09 G. A. Peña , G. N. Candlish

We study the behavior of n-point functions of the primordial curvature perturbations, assuming our observed Universe is only a subset of a larger space with statistically homogeneous and isotropic perturbations. If the larger space has…

Cosmology and Nongalactic Astrophysics · Physics 2013-07-25 Elliot Nelson , Sarah Shandera

It has long been known how to analytically relate the clustering properties of the collapsed structures (halos) to those of the underlying dark matter distribution for Gaussian initial conditions. Here we apply the same approach to…

Astrophysics · Physics 2010-11-11 Sabino Matarrese , Licia Verde

We consider the description of the clustering of halos for physically-motivated types of non-Gaussian initial conditions. In particular we include non-Gaussianity of the type arising from single field slow-roll, multi fields, curvaton…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 Licia Verde , Sabino Matarrese

Motivated by the properties of early universe scenarios that produce observationally large local non-Gaussianity, we perform N-body simulations with non-Gaussian initial conditions from a generalized local ansatz. The bispectra are…

Cosmology and Nongalactic Astrophysics · Physics 2011-03-18 Sarah Shandera , Neal Dalal , Dragan Huterer

Whilst current observational evidence favors a close-to-Gaussian spectrum of primordial perturbations, there exist many models of the early Universe that predict this distribution to have exponentially enhanced or suppressed tails. In this…

Cosmology and Nongalactic Astrophysics · Physics 2024-06-25 William R. Coulton , Oliver H. E. Philcox , Francisco Villaescusa-Navarro

We use the statistics of regions above or below a temperature threshold (excursion sets) to study the cosmic microwave background (CMB) anisotropy in models with primordial non-Gaussianity of the local type. By computing the full-sky…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 Graziano Rossi , Pravabati Chingangbam , Changbom Park

We investigate the origin of the large clustering signal detected in the angular distribution of the radio sources in the TGSS catalog. To do so, we cross-correlate the angular position of the radio sources with the Cosmic Microwave…

Cosmology and Nongalactic Astrophysics · Physics 2023-03-08 Giulia Piccirilli , Marina Migliaccio , Enzo Branchini , Arianna Dolfi