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Related papers: Optimal constraint on g_NL from CMB

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Measuring the small primordial nonGaussianity (PNG) predicted by cosmic inflation theories may help diagnose them. The detectability of PNG by its imprint on the 21cm power spectrum from the epoch of reionization is reassessed here in terms…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-15 Yi Mao , Anson D'Aloisio , Jun Zhang , Paul R. Shapiro

This paper investigates Gaussian copula mixture models (GCMM), which are an extension of Gaussian mixture models (GMM) that incorporate copula concepts. The paper presents the mathematical definition of GCMM and explores the properties of…

Machine Learning · Computer Science 2023-05-25 Ke Wan , Alain Kornhauser

The statistical analysis of the soon to come Planck satellite CMB data will help set tighter bounds on major cosmological parameters. On the way, a number of practical difficulties need to be tackled, notably that several other…

Astrophysics · Physics 2009-11-13 P. Abrial , Y. Moudden , J. -L. Starck , J. Fadili , J. Delabrouille , M. K. Nguyen

The cosmic microwave background (CMB) bispectrum is a well-known probe of the non-Gaussianity of primordial perturbations. Just as the intervening large-scale structure modifies the CMB angular power spectrum through weak gravitational…

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

We develop a needlet approach to estimate the amplitude of general (including non-separable) bispectra and trispectra in the cosmic microwave background, and apply this to the WMAP 9-year data. We obtain estimates for the `orthogonal'…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-17 Donough Regan , Mateja Gosenca , David Seery

We introduce an alternative parametrisation for the scale dependence of the non-linearity parameter $f_{\rm NL}$ in quasi-local models of non-Gaussianity. Our parametrisation remains valid when $f_{\rm NL}$ changes sign, unlike the commonly…

Cosmology and Nongalactic Astrophysics · Physics 2015-11-02 Christian T. Byrnes , Ewan R. M. Tarrant

Primordial non-Gaussianity arising from inflationary models is a unique probe of non-trivial dynamics of the inflaton field and its interactions with other fields. Often when examining and constraining the scalar non-Gaussianity arising…

Cosmology and Nongalactic Astrophysics · Physics 2023-04-17 Barnali Das , H. V. Ragavendra

We present posterior sample-based cosmic microwave background (CMB) constraints from Planck LFI and WMAP observations derived through global end-to-end Bayesian processing. We use these samples to study correlations between CMB, foreground,…

Weak gravitational lensing has become a common tool to constrain the cosmological model. The majority of the methods to derive constraints on cosmological parameters use second-order statistics of the cosmic shear. Despite their success,…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 Sandrine Pires , Adrienne Leonard , Jean-Luc Starck

We compare cosmological parameters from different Planck sky maps and likelihood pipelines, assessing robustness of cosmological results with respect to the choice of the latest Planck maps-likelihood combination. We show that, for the…

Cosmology and Nongalactic Astrophysics · Physics 2026-02-27 Hidde Jense , Marc Viña , Erminia Calabrese , J. Colin Hill

We evaluate the contribution of cosmic microwave background (CMB) polarization spectra to cosmological parameter constraints. We produce cosmological parameters using high-quality CMB polarization data from the ground-based QUaD experiment…

We analyze WMAP 3 year data using the one-point distribution functions to probe the non-Gaussianity in the Cosmic Microwave Background (CMB) Anisotropy data. Computer simulations are performed to determine the uncertainties of the results.…

Astrophysics · Physics 2007-10-16 E. Jeong , G. F. Smoot

Upcoming stage 4 surveys, such as the Simons Observatory, LSST, and Euclid, are poised to measure weak gravitational lensing of the Cosmic Microwave Background (CMB) and galaxies with unprecedented precision. While the power spectrum is the…

Cosmology and Nongalactic Astrophysics · Physics 2026-05-07 Jonas Frugte , P. Daniel Meerburg

It is well known that there have been many numerical algorithms for solving nonsmooth minimax problems, numerical algorithms for nonsmooth minimax problems with joint linear constraints are very rare. This paper aims to discuss optimality…

Optimization and Control · Mathematics 2022-04-21 Yu-Hong Dai , Jiani Wang , Liwei Zhang

Since the inhomogeneous instrument noise can produce extra non-Gaussianity in the CMB anisotropy, its effect should be carefully subtracted in the primordial non-Gaussianity estimation. We calculate the probability distribution function of…

Astrophysics · Physics 2009-02-23 B. Yu , T. Lu

Although the broad outlines of the appropriate pipeline for cosmological likelihood analysis with CMB data has been known for several years, only recently have we had to contend with the full, large-scale, computationally challenging…

Astrophysics · Physics 2009-11-10 Andrew H. Jaffe , J. R. Bond , P. G. Ferreira , L. E. Knox

We describe the details of the binned bispectrum estimator as used for the official 2013 and 2015 analyses of the temperature and polarization CMB maps from the ESA Planck satellite. The defining aspect of this estimator is the…

Cosmology and Nongalactic Astrophysics · Physics 2016-06-02 Martin Bucher , Benjamin Racine , Bartjan van Tent

High-dimensional datasets are frequently subject to contamination by outliers and heavy-tailed noise, which can severely bias standard regularized estimators like the Lasso. While Maximum Mean Discrepancy (MMD) has recently been introduced…

Methodology · Statistics 2026-02-25 Xiaoning Kang , Lulu Kang

A detection or non detection of primordial non--Gaussianity (NG) by using the cosmic microwave background radiation (CMB) is a possible way to break the degeneracy of early universe models. Since a single statistical estimator hardly can be…

Cosmology and Nongalactic Astrophysics · Physics 2013-05-29 W. A. Cardona , A. Bernui , M. J. Reboucas
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