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Related papers: Non-Gaussian Error in Galaxy Survey (Part 1)

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Surveys of the matter distribution contain `fossil' information on possible non-Gaussianity that is generated in the primordial Universe. This primordial signal survives only on the largest scales where cosmic variance is strongest. By…

Cosmology and Nongalactic Astrophysics · Physics 2024-07-10 Sheean Jolicoeur , Roy Maartens , Simthembile Dlamini

We explore and compare the performances of two nonlinear correction and scale-dependent biasing models for the extraction of cosmological information from galaxy power spectrum data, especially in the context of beyond-LCDM cosmologies. The…

Astrophysics · Physics 2008-11-26 Jan Hamann , Steen Hannestad , Alessandro Melchiorri , Yvonne Y. Y. Wong

The description of the abundance and clustering of halos for non-Gaussian initial conditions has recently received renewed interest, motivated by the forthcoming large galaxy and cluster surveys, which can potentially yield constraints of…

Cosmology and Nongalactic Astrophysics · Physics 2010-11-02 M. Grossi , L. Verde , C. Carbone , K. Dolag , E. Branchini , F. Iannuzzi , S. Matarrese , L. Moscardini

Primordial non-Gaussianity of local type is known to produce a scale-dependent contribution to the galaxy bias. Several classes of multi-field inflationary models predict non-Gaussian bias which is stochastic, in the sense that dark matter…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-05 Simone Ferraro , Kendrick M. Smith

The scale-dependent galaxy bias generated by primordial non-Gaussianity (PNG) can be used to detect and constrain deviations from standard single-field inflation. The strongest signal is expected in the local model for PNG, where the…

Cosmology and Nongalactic Astrophysics · Physics 2016-01-29 Nina Roth , Cristiano Porciani

We investigate the clustering of halos in cosmological models starting with general local-type non-Gaussian primordial fluctuations. We employ multiple Gaussian fields and add local-type non-Gaussian corrections at arbitrary order to cover…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 Takahiro Nishimichi

The rapidly increasing statistical power of cosmological imaging surveys requires us to reassess the regime of validity for various approximations that accelerate the calculation of relevant theoretical predictions. In this paper, we…

We introduce a method for performing a robust Bayesian analysis of non-Gaussianity present in pulsar timing data, simultaneously with the pulsar timing model, and additional stochastic parameters such as those describing red spin noise and…

Instrumentation and Methods for Astrophysics · Physics 2014-09-19 Lindley Lentati , Michael P. Hobson , Paul Alexander

We consider robust covariance estimation with group symmetry constraints. Non-Gaussian covariance estimation, e.g., Tyler scatter estimator and Multivariate Generalized Gaussian distribution methods, usually involve non-convex minimization…

Machine Learning · Statistics 2013-06-19 Ilya Soloveychik , Ami Wiesel

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

We develop the halo model of large-scale structure as an accurate tool for probing primordial non-Gaussianity. In this study we focus on understanding the matter clustering at several redshifts. The primordial non-Gaussianity is modeled as…

Cosmology and Nongalactic Astrophysics · Physics 2011-08-09 Robert E. Smith , Vincent Desjacques , Laura Marian

We explore a systematic approach to the analysis of primordial non-Gaussianity using fluctuations in temperature and polarization of the Cosmic Microwave Background (CMB). Following Munshi & Heavens (2009), we define a set of power-spectra…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 Dipak Munshi , Peter Coles , Asantha Cooray , Alan Heavens , Joseph Smidt

Our goals are (i) to search for BAO and large-scale structure in current QSO survey data and (ii) to use these and simulation/forecast results to assess the science case for a new, >10x larger, QSO survey. We first combine the SDSS, 2QZ and…

Cosmology and Nongalactic Astrophysics · Physics 2012-02-01 U. Sawangwit , T. Shanks , S. M. Croom , M. J. Drinkwater , S. Fine , D. Parkinson , Nicholas P. Ross

The power spectrum of the nonlinearly evolved large-scale mass distribution recovers only a minority of the information available on the mass fluctuation amplitude. We investigate the recovery of this information in 2D "slabs" of the mass…

Cosmology and Nongalactic Astrophysics · Physics 2022-12-14 Lucas Porth , Gary M. Bernstein , Robert E. Smith , Abigail J. Lee

We re-examine a genuine power of weak lensing bispectrum tomography for constraining cosmological parameters, when combined with the power spectrum tomography, based on the Fisher information matrix formalism. To account for the full…

Cosmology and Nongalactic Astrophysics · Physics 2013-06-21 Issha Kayo , Masahiro Takada

We investigate the statistical power of higher-order statistics and cross-correlation statistics to constrain the primordial non-Gaussianity from the imaging surveys. In particular, we consider the local-type primordial non- Gaussianity and…

Cosmology and Nongalactic Astrophysics · Physics 2016-06-08 Ichihiko Hashimoto , Atsushi Taruya , Takahiko Matsubara , Toshiya Namikawa , Shuichiro Yokoyama

The fluctuations generated by Inflation are nearly Gaussian in the simplest models, but may be non-Gaussian in more complex models, potentially leading to signatures in the late Universe. In particular, local type primordial non-Gaussianity…

Cosmology and Nongalactic Astrophysics · Physics 2025-09-03 Mponeng Kopana , Sheean Jolicoeur , Roy Maartens

The likelihood function is a crucial element of parameter estimation. In analyses of galaxy overdensities and weak lensing shear, one often approximates the likelihood of the power spectrum with a Gaussian distribution. The posterior…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-16 L. Sun , Q. Wang , H. Zhan

We use cosmological N-body simulations to investigate whether measurements of the moments of large-scale structure can yield constraints on primordial non-Gaussianity. We measure the variance, skewness, and kurtosis of the evolved density…

Cosmology and Nongalactic Astrophysics · Physics 2014-07-24 Qingqing Mao , Andreas A. Berlind , Cameron K. McBride , Robert J. Scherrer , Roman Scoccimarro , Marc Manera

Extracting the three dimensional power spectrum from the 2D distribution of galaxies has become a standard tool of cosmology. This extraction requires some assumptions about the scaling of the power spectrum with redshift; all treatments to…

Astrophysics · Physics 2007-05-23 R. Scranton , S. Dodelson
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