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Related papers: Non-Gaussian error bars in galaxy surveys -- II

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Cosmic microwave background observations are most commonly analyzed by estimating the power spectrum. In the limit where the CMB statistics are perfectly Gaussian, this extracts all the information, but the CMB also contains detectable…

Cosmology and Nongalactic Astrophysics · Physics 2011-11-09 Kendrick M. Smith

To investigate and specify the statistical properties of cosmological fields with particular attention to possible non-Gaussian features, accurate formulae for the bispectrum and the bispectrum covariance are required. The bispectrum is the…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-30 Sandra Martin , Peter Schneider , Patrick Simon

The greatest challenge in the interpretation of galaxy clustering data from any surveys is galaxy bias. Using a simple Fisher matrix analysis, we show that the bispectrum provides an excellent determination of linear and non-linear bias…

Astrophysics · Physics 2008-11-26 Emiliano Sefusatti , Eiichiro Komatsu

Detecting and measuring a non-Gaussian signature of primordial origin in the density field is a major science goal of next-generation galaxy surveys. The signal will permit us to determine primordial physics processes and constrain models…

Cosmology and Nongalactic Astrophysics · Physics 2023-02-15 Adam Andrews , Jens Jasche , Guilhem Lavaux , Fabian Schmidt

We address the dual challenge of estimating deviations from Gaussianity arising in models of the Early Universe, whilst retaining information necessary to assess whether a detection of non-Gaussianity is primordial. We do this by…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 Dipak Munshi , Alan Heavens

In paper I (Yu et al. [1]), we show through N-body simulation that a local monotonic Gaussian transformation can significantly reduce non-Gaussianity in a noise-free lensing convergence field. This makes the Gaussianization a promising…

Cosmology and Nongalactic Astrophysics · Physics 2012-07-17 Yu Yu , Pengjie Zhang , Weipeng Lin , Weiguang Cui , James N. Fry

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 present an algorithm for quickly generating multiple realizations of N-body simulations to be used, for example, for cosmological parameter estimation from surveys of large-scale structure. Our algorithm uses a new method to resample the…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 Michael D. Schneider , Shaun Cole , Carlos S. Frenk , Istvan Szapudi

We develop a purely mathematical tool to recover some of the information lost in the non-linear collapse of large-scale structure. From a set of 141 simulations of dark matter density fields, we construct a non-linear Weiner filter in order…

Cosmology and Nongalactic Astrophysics · Physics 2011-01-27 Tong-Jie Zhang , Hao-Ran Yu , Joachim Harnois-Déraps , Ilana MacDonald , Ue-Li Pen

Recent simulations show the Epoch of Reionization (EoR) 21-cm signal to be inherently non-Gaussian whereby the error covariance matrix $\mathbf{C}_{ij}$ of the 21-cm power spectrum (PS) contains a trispectrum contribution that would be…

Cosmology and Nongalactic Astrophysics · Physics 2019-07-01 Abinash Kumar Shaw , Somnath Bharadwaj , Rajesh Mondal

The estimation of cosmological constraints from observations of the large scale structure of the Universe, such as the power spectrum or the correlation function, requires the knowledge of the inverse of the associated covariance matrix,…

Cosmology and Nongalactic Astrophysics · Physics 2015-11-04 Dante J. Paz , Ariel G. Sanchez

The Bayesian gravitational shear estimation algorithm developed by Bernstein and Armstrong (2014) can potentially be used to overcome multiplicative noise bias and recover shear using very low signal-to-noise ratio (S/N) galaxy images. In…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-19 Erin S. Sheldon

Using the 5 year WMAP data, we re-investigate claims of non-Gaussianities and asymmetries detected in local curvature statistics of the 1 year WMAP data. In Hansen et al 2004, it was found that the northern ecliptic hemisphere was…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 Øystein Rudjord , Nicolaas E. Groeneboom , Frode K. Hansen , Paolo Cabella

The present spatial distribution of galaxies in the Universe is non-Gaussian, with 40% skewness in 50 Mpc/h spheres, and remarkably little is known about the information encoded in it about cosmological parameters beyond the power spectrum.…

Astrophysics · Physics 2008-11-26 Emiliano Sefusatti , Martin Crocce , Sebastian Pueblas , Roman Scoccimarro

Dedicated 'Stage IV' observatories will soon observe the entire extragalactic sky, to measure the 'cosmic shear' distortion of galaxy shapes by weak gravitational lensing. To measure the apparent shapes of those galaxies, we present an…

Cosmology and Nongalactic Astrophysics · Physics 2022-02-08 Xiangchong Li , Yin Li , Richard Massey

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 forthcoming generation of wide-field galaxy surveys will probe larger volumes and galaxy densities, thus allowing for a much larger signal-to-noise ratio for higher-order clustering statistics, in particular the galaxy bispectrum.…

Cosmology and Nongalactic Astrophysics · Physics 2020-04-15 Azadeh Moradinezhad Dizgah , Hayden Lee , Marcel Schmittfull , Cora Dvorkin

We compare the efficiency of weak lensing-selected galaxy clusters counts and of the weak lensing bispectrum at capturing non-Gaussian features in the dark matter distribution. We use the halo model to compute the weak lensing power…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 Joel Berge , Adam Amara , Alexandre Refregier

We present a framework to compute non-Gaussian likelihoods for two-point correlation functions. The non-Gaussianity is most pronounced on large scales that will be well-measured by stage-IV weak-lensing surveys. We show how such a…

Cosmology and Nongalactic Astrophysics · Physics 2026-04-09 Veronika Oehl , Tilman Tröster

We study the lensing convergence power spectrum and its covariance for a standard LCDM cosmology. We run 400 cosmological N-body simulations and use the outputs to perform a total of 1000 independent ray-tracing simulations. We compare the…

Cosmology and Nongalactic Astrophysics · Physics 2012-03-12 Masanori Sato , Takashi Hamana , Ryuichi Takahashi , Masahiro Takada , Naoki Yoshida , Takahiko Matsubara , Naoshi Sugiyama
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