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相关论文: An improved estimator for non-Gaussianity in cosmi…

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An optimal method to constrain the non-linearity parameter g_NL of the local-type non-Gaussianity from CMB data is proposed. Our optimal estimator for g_NL is separable and can be efficiently computed in real space. Combining the exact…

宇宙学与河外天体物理 · 物理学 2013-09-03 Toyokazu Sekiguchi , Naoshi Sugiyama

A new method for estimating the angular power spectrum C_l from cosmic microwave background (CMB) maps is presented, which has the following desirable properties: (1) It is unbeatable in the sense that no other method can measure C_l with…

天体物理学 · 物理学 2009-10-07 Max Tegmark

The presence of astrophysical emissions in microwave observations forces us to perform component separation to extract the Cosmic Microwave Background (CMB) signal. However, even in the most optimistic cases, there are still strongly…

宇宙学与河外天体物理 · 物理学 2024-09-26 C. Gimeno-Amo , E. Martínez-González , R. B. Barreiro

Due to the integrated Sachs-Wolfe (ISW) effect, cosmic microwave background (CMB) temperature and polarization fluctuations are correlated with the gravitational lensing potential. Famously, this induces a CMB three-point function, whose…

宇宙学与河外天体物理 · 物理学 2025-06-17 Oliver H. E. Philcox , J. Colin Hill

The Quadratic Maximum Likelihood estimator can be used to reconstruct the Cosmic Microwave Background (CMB) power spectra with minimal error bars. Still, it requires an accurate estimate of the datasets noise covariance matrix in order to…

宇宙学与河外天体物理 · 物理学 2018-11-28 S. Vanneste , S. Henrot-Versillé , T. Louis , M. Tristram

I develop a method for assessing the ability of an instrument, coupled with an observing strategy, to measure the angular power spectrum of the cosmic microwave background (CMB). It allows for efficient calculation of expected parameter…

天体物理学 · 物理学 2009-10-28 Lloyd Knox

We investigate optimization strategies to measure primordial non-Gaussianity with future spectroscopic surveys. We forecast measurements coming from the 3D galaxy power spectrum and compute constraints on primordial non-Gaussianity…

宇宙学与河外天体物理 · 物理学 2015-08-26 Alvise Raccanelli , Olivier Dore , Neal Dalal

We study Minkowski Functionals as probes of primordial non-Gaussianity in the Cosmic Microwave Background, specifically for the estimate of the primordial `local' bi-spectrum parameter f_NL, with instrumental parameters which should be…

宇宙学与河外天体物理 · 物理学 2015-06-11 Anne Ducout , François Bouchet , Stéphane Colombi , Dmitri Pogosyan , Simon Prunet

Two different predictions for the primordial curvature fluctuation bispectrum are compared through their effects on the Cosmic Microwave Background temperature fluctuations. The first has a local form described by a single parameter f_{NL}.…

天体物理学 · 物理学 2009-06-23 Ian G Moss , Chris M Graham

Weak gravitational lensing of the cosmic microwave background (CMB) is a powerful probe of cosmology, providing insight into structure formation and the evolution of the universe. Current and upcoming CMB experiments such as SPT-3G and the…

宇宙学与河外天体物理 · 物理学 2026-03-30 Yuka Nakato , W. L. Kimmy Wu , Ana Carolina Silva Oliveira , Yuuki Omori , Abhishek S. Maniyar

It is known that the Cosmic Microwave Background (CMB) temperature fluctuations are modified by gravitational lensing since the angular positions of photons are altered by the metric perturbations. We reconsider this effect in the context…

广义相对论与量子宇宙学 · 物理学 2021-02-03 Ali Kaya

Our view of the last-scattering surface in the cosmic microwave background (CMB) is obscured by secondary anisotropies, sourced by scattering, extragalactic emission and gravitational processes between recombination and observation. Whilst…

宇宙学与河外天体物理 · 物理学 2023-05-10 William Coulton , Alexander Miranthis , Anthony Challinor

Cosmic microwave background (CMB) temperature anisotropies follow a Gaussian statistical distribution in the standard inflationary model, but there are non-Gaussian contributions due to astrophysical foregrounds. The detection of the…

天体物理学 · 物理学 2009-11-11 F. Argueso , J. L. Sanz , R. B. Barreiro , D. Herranz , J. Gonzalez-Nuevo

The search for primordial gravitational waves in the Cosmic Microwave Background (CMB) will soon be limited by our ability to remove the lensing contamination to $B$-mode polarization. The often-used quadratic estimator for lensing is known…

宇宙学与河外天体物理 · 物理学 2021-01-04 Marius Millea , Ethan Anderes , Benjamin D. Wandelt

In this paper we propose a new statistic capable of detecting non-Gaussianity in the CMB. The statistic is defined in Fourier space, and therefore naturally separates angular scales. It consists of taking another Fourier transform, in…

天体物理学 · 物理学 2010-04-08 Alex Lewin , Andreas Albrecht , Joao Magueijo

Gravitational lensing of the cosmic microwave background (CMB), a long-standing prediction of the standard cosmolgical model, is ultimately expected to be an important source of cosmological information, but first detection has not been…

天体物理学 · 物理学 2008-12-18 Kendrick M. Smith , Oliver Zahn , Olivier Dore

Many inflation models predict that primordial density perturbations have a nonzero three-point correlation function, or bispectrum in Fourier space. Of the several possibilities for this bispectrum, the most commmon is the local-model…

宇宙学与河外天体物理 · 物理学 2015-07-01 Razieh Emami , Emanuela Dimastrogiovanni , Jens Chluba , Marc Kamionkowski

An improved method for subtracting contaminants from Cosmic Microwave Background (CMB) sky maps is presented, and used to estimate how well future experiments will be able to recover the primordial CMB fluctuations. We find that the naive…

天体物理学 · 物理学 2015-06-24 Max Tegmark , George Efstathiou

We present a detailed implementation of two bispectrum estimation methods which can be applied to general non-separable primordial and CMB bispectra. The method exploits bispectrum mode decompositions on the domain of allowed wavenumber or…

宇宙学与河外天体物理 · 物理学 2014-11-20 J. R. Fergusson , M. Liguori , E. P. S. Shellard

Two of the most commonly used tools to constrain the primordial non-Gaussianity are the bispectrum and the Minkowski functionals of CMB temperature anisotropies. These two measures of non-Gaussianity in principle provide distinct (though…

宇宙学与河外天体物理 · 物理学 2015-03-26 Wenjuan Fang , Adam Becker , Dragan Huterer , Eugene A. Lim