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相关论文: The Impact of Secondary non-Gaussianities in the C…

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We discuss the four-point correlation function, or the trispectrum in Fourier space, of CMB temperature and polarization anisotropies due to the weak gravitational lensing effect by intervening large scale structure. We discuss the squared…

天体物理学 · 物理学 2009-11-07 Asantha Cooray , Michael Kesden

We discuss the real-space moments of temperature anisotropies in the cosmic microwave background (CMB) due to weak gravitational lensing by intervening large-scale structure. We show that if the probability distribution function of…

天体物理学 · 物理学 2009-11-07 Michael Kesden , Asantha Cooray , Marc Kamionkowski

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

We develop optimised estimators of two sorts of power spectra for fields defined on the sky, in the presence of partial sky coverage. The first is the cross-power spectrum of two fields on the sky; the second is the skew spectrum of three…

宇宙学与河外天体物理 · 物理学 2015-05-13 Dipak Munshi , Patrick Valageas , Asantha Cooray , Alan Heavens

Gravitational lensing, caused by matter perturbations along the line-of-sight to the last scattering surface, can modify the shape of the cosmic microwave background (CMB) anisotropy power spectrum. We discuss the detectability of lensing…

天体物理学 · 物理学 2009-10-30 R. Stompor , G. Efstathiou

We study how well the Gaussian approximation is valid for computing the covariance matrices of the convergence power and bispectrum in weak gravitational lensing analyses. We focus on its impact on the cosmological parameter estimations by…

宇宙学与河外天体物理 · 物理学 2015-06-12 Masanori Sato , Takahiro Nishimichi

Weak gravitational lensing of the Cosmic Microwave Background (CMB) changes CMB statistics in a nontrivial way, allowing for reconstruction of the lensing potential and the use of these reconstructed maps in determining cosmological…

宇宙学与河外天体物理 · 物理学 2023-08-23 Cynthia Trendafilova

We investigate the weak lensing corrections to the cosmic microwave background temperature anisotropies considering effects beyond the Born approximation. To this aim, we use the small deflection angle approximation, to connect the lensed…

宇宙学与河外天体物理 · 物理学 2016-09-20 Giovanni Marozzi , Giuseppe Fanizza , Enea Di Dio , Ruth Durrer

The Cosmic microwave background (CMB) anisotropies predicted by two cosmological models are compared, one of them is the standard model of general relativity with cold dark matter and cosmological constant, whereas the second model is based…

宇宙学与河外天体物理 · 物理学 2024-01-19 Roberto Dale , Diego Sáez

We show that modified gravity presents distinctive nonlinear features on the Cosmic Microwave Background (CMB) anisotropies comparing with General Relativity (GR). We calculate the contribution to the CMB non-Gaussianity from nonlinear…

广义相对论与量子宇宙学 · 物理学 2011-08-09 Xian Gao

The next generation of ground-based CMB experiments aim to measure temperature and polarization fluctuations up to $\ell_{\rm max} \approx 5000$ over half of the sky. Combined with Planck data on large scales, this will provide improved…

宇宙学与河外天体物理 · 物理学 2020-07-01 William R. Coulton , P. Daniel Meerburg , David G. Baker , Selim Hotinli , Adriaan J. Duivenvoorden , Alexander van Engelen

We examine the biases induced on cosmological parameters when the presence of secondary anisotropies is not taken into account in Cosmic Microwave Background analyses. We first develop an exact analytical expression for computing the biases…

天体物理学 · 物理学 2009-04-16 Nicolas Taburet , Nabila Aghanim , Marian Douspis , Mathieu Langer

Nonlinear gravitational effects of large-scale inhomogeneities on Cosmic Microwave Background (CMB) anisotropies are studied. based on the relativistic second-order theory of perturbations in nonzero-Lambda flat cosmological models, which…

天体物理学 · 物理学 2009-11-11 Kenji Tomita

Weak gravitational lensing has several important effects on the cosmic microwave background (CMB): it changes the CMB power spectra, induces non-Gaussianities, and generates a B-mode polarization signal that is an important source of…

天体物理学 · 物理学 2007-05-23 Antony Lewis , Anthony Challinor

We develop a new, efficient code for solving the second-order Einstein-Boltzmann equations, and use it to estimate the intrinsic CMB non-Gaussianity arising from the non-linear evolution of density perturbations. The full calculation…

宇宙学与河外天体物理 · 物理学 2015-06-12 Guido W. Pettinari , Christian Fidler , Robert Crittenden , Kazuya Koyama , David Wands

Weak lensing effects are known to introduce non-linear couplings in CMB temperature maps. In inflationary scenario, the primary CMB anisotropies are expected to form a 2D Gaussian map, for which, the probability distribution function of the…

天体物理学 · 物理学 2011-05-23 F. Bernardeau

We use numerical simulation of cosmological reionization to calculate the secondary CMB anisotropies in a representative flat low density cosmological model. We show that the kinetic Sunyaev-Zel'dovich effect (scattering off of moving…

天体物理学 · 物理学 2009-10-31 Nickolay Y. Gnedin , Andrew H. Jaffe

We review several aspects of the Sunyaev-Zel'dovich (SZ) effect associated with the large scale baryon distribution and its characteristic signatures in the statistics of cosmic microwave background (CMB) anisotropies. We discuss (1) the…

天体物理学 · 物理学 2007-05-23 Asantha Cooray , Daniel Baumann , Kris Sigurdson

We study statistical anisotropies generated in the observed two-point function of the cosmic microwave background (CMB) fluctuations if the primordial statistics are non-Gaussian. Focusing on the dipole modulations of the anisotropies, we…

宇宙学与河外天体物理 · 物理学 2018-07-17 Saroj Adhikari , Anne-Sylvie Deutsch , Sarah Shandera

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