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Related papers: Effects of Scale-Dependent Non-Gaussianity on Cosm…

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We show that the ability to probe primordial non-Gaussianity with cluster counts is drastically improved by adding the excess variance of counts which contains information on the clustering. The conflicting dependences of changing the mass…

Cosmology and Nongalactic Astrophysics · Physics 2010-04-15 Masamune Oguri

We predict the biasing and clustering properties of galaxy clusters that are expected to be observed in the catalogues produced by two forthcoming X-ray and Sunyaev-Zel'dovich effect surveys. We study a set of flat cosmological models where…

Cosmology and Nongalactic Astrophysics · Physics 2010-11-02 C. Fedeli , L. Moscardini , S. Matarrese

A description of CMB temperature fluctuations beyond the power spectrum is important for verifying models of structure formation, especially in view of forthcoming high-resolution observations. We argue that higher-order statistics of…

Astrophysics · Physics 2007-05-23 S. Winitzki , J. H. P. Wu

We consider gravitational clustering from primoridal non-Gaussian fluctuations provided by a $\chi^2$ model, as motivated by some models of inflation. The emphasis is in signatures that can be used to constrain this type of models from…

Astrophysics · Physics 2009-10-31 Roman Scoccimarro

Measurements of the non-Gaussianity of the primordial density field have the power to considerably improve our understanding of the physics of inflation. Indeed, if we can increase the precision of current measurements by an order of…

Cosmology and Nongalactic Astrophysics · Physics 2016-06-15 Matteo Tellarini , Ashley J. Ross , Gianmassimo Tasinato , David Wands

We investigate the constraints on primordial non-Gaussianity with varied bispectrum shapes that can be derived from the power spectrum of galaxies and clusters of galaxies detected in future wide field optical/near-infrared surveys. Having…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 Cosimo Fedeli , Carmelita Carbone , Lauro Moscardini , Andrea Cimatti

Cosmic inflation provides a mechanism for generating the early density perturbations that seeded the large-scale structures we see today. Primordial non-Gaussianity is among the most promising of few observational tests of physics at this…

Cosmology and Nongalactic Astrophysics · Physics 2011-10-10 Marilena LoVerde , Simone Ferraro , Kendrick M. Smith

Minkowski Functionals (MFs) are topological statistics that have become one of many standard tools used for investigating the statistical properties of cosmological random fields. They have found regular use in studies of departures from…

Cosmology and Nongalactic Astrophysics · Physics 2012-09-20 Geraint Pratten , Dipak Munshi

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

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

The primordial non-Gaussianity parameters fNL and tauNL may be scale-dependent. We investigate the capability of future measurements of the CMB mu-distortion, which is very sensitive to small scales, and of the large-scale halo bias to test…

Cosmology and Nongalactic Astrophysics · Physics 2013-03-27 Matteo Biagetti , Hideki Perrier , Antonio Riotto , Vincent Desjacques

Local-type primordial non-gaussianity generates a distinctive term in the clustering of tracers of large-scale structure, behaving as $k^{-2}$ at small wavenumbers $k$. In order to use this signal in a sample of galaxies to measure the…

Cosmology and Nongalactic Astrophysics · Physics 2025-03-28 Neal Dalal , Will J. Percival

A key challenge in the search for primordial B-modes is the presence of polarized Galactic foregrounds, especially thermal dust emission. Power-spectrum-based analysis methods generally assume the foregrounds to be Gaussian random fields…

Cosmology and Nongalactic Astrophysics · Physics 2023-12-21 Irene Abril-Cabezas , Carlos Hervías-Caimapo , Sebastian von Hausegger , Blake D. Sherwin , David Alonso

A detection of primordial non-Gaussianity could transform our understanding of the fundamental theory of inflation. The precision promised by upcoming CMB and large-scale structure surveys raises a natural question: if a detection given a…

Cosmology and Nongalactic Astrophysics · Physics 2014-03-04 Joyce Byun , Rachel Bean

We calculate the bispectrum, B_g(k_1,k_2,k_3), Fourier transform of the three-point function of density peaks (e.g., galaxies), using two different methods: the Matarrese-Lucchin-Bonometto formula and the locality of galaxy bias. The…

Cosmology and Nongalactic Astrophysics · Physics 2009-09-28 Donghui Jeong , Eiichiro Komatsu

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 2009-09-03 T. R. Seshadri , Kandaswamy Subramanian

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

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…

We study the bispectrum of the primordial curvature perturbation on uniform-density hypersurfaces generated by a kind of the noncanonical warm inflation, wherein the inflation is provided by a noncanonical scalar inflaton field that is…

General Relativity and Quantum Cosmology · Physics 2015-04-09 Xiao-Min Zhang , Jian-Yang Zhu

We consider cosmological inflationary models in which vector fields play some role in the generation of the primordial curvature perturbation $\zeta$. Such models are interesting because the involved vector fields naturally seed statistical…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-19 Juan P. Beltran Almeida , Yeinzon Rodriguez , Cesar A. Valenzuela-Toledo
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