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相关论文: Wavelet domain Bayesian denoising of string signal…

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Cosmic strings are a well-motivated extension to the standard cosmological model and could induce a subdominant component in the anisotropies of the cosmic microwave background (CMB), in addition to the standard inflationary component. The…

天体物理仪器与方法 · 物理学 2017-09-18 J. D. McEwen , S. M. Feeney , H. V. Peiris , Y. Wiaux , C. Ringeval , F. R. Bouchet

We propose an algorithm for the reconstruction of the signal induced by cosmic strings in the cosmic microwave background (CMB), from radio-interferometric data at arcminute resolution. Radio interferometry provides incomplete and noisy…

宇宙学与河外天体物理 · 物理学 2015-05-14 Y. Wiaux , G. Puy , P. Vandergheynst

Searching for and charactering the non-Gaussianity (NG) of a given field has been a vital task in many fields of science, because we expect the consequences of different physical processes to carry different statistical properties. Here we…

天体物理学 · 物理学 2007-05-23 Jiun-Huei Proty Wu

We investigate the use of wavelet transforms in detecting and characterising non-Gaussian structure in maps of the cosmic microwave background (CMB). We apply the method to simulated maps of the Kaiser-Stebbins effect due to cosmic strings…

天体物理学 · 物理学 2009-10-31 MP Hobson , AW Jones , AN Lasenby

We briefly review certain aspects of cosmic microwave background anisotropies as generated in passive and active models of structure formation. We then focus on cosmic strings based models and discuss their status in the light of current…

天体物理学 · 物理学 2009-11-07 Alejandro Gangui , Levon Pogosian , Serge Winitzki

The cosmic microwave background (CMB) is a significant source of knowledge about the origin and evolution of our universe. However, observations of the CMB are contaminated by foreground emissions, obscuring the CMB signal and reducing its…

机器学习 · 计算机科学 2023-02-27 Jadie Adams , Steven Lu , Krzysztof M. Gorski , Graca Rocha , Kiri L. Wagstaff

We study the problem of searching for cosmic string signal patterns in the present high resolution and high sensitivity observations of the Cosmic Microwave Background (CMB). This article discusses a technique capable of recognizing…

宇宙学与河外天体物理 · 物理学 2014-11-20 E. Jeong , Carlo Baccigalupi , G. F. Smoot

We report on a current investigation of the anisotropy pattern induced by cosmic strings on the cosmic microwave background radiation (MBR). We have numerically evolved a network of cosmic strings from a redshift of $Z = 100$ to the present…

天体物理学 · 物理学 2007-05-23 B. Allen , R. R. Caldwell , E. P. S. Shellard , A. Stebbins , S. Veeraraghavan

There exists various proposals to detect cosmic strings from Cosmic Microwave Background (CMB) or 21 cm temperature maps. Current proposals do not aim to find the location of strings on sky maps, all of these approaches can be thought of as…

宇宙学与河外天体物理 · 物理学 2017-09-01 Razvan Ciuca , Oscar F. Hernández

We propose a new general method of extracting non-Gaussian features in a given field. It sets the mean of the field to zero and renormalizes its Fourier (or multipole) power to white noise, while keeping the phase information unchanged.…

天体物理学 · 物理学 2007-05-23 Jiun-Huei Proty Wu

Analysis and denoising of Cosmic Microwave Background (CMB) maps are performed using wavelet multiresolution techniques. The method is tested on $12^{\circ}.8\times 12^{\circ}.8$ maps with resolution resembling the experimental one expected…

天体物理学 · 物理学 2009-10-31 J. L. Sanz , F. Argueso , L. Cayon , E. Martinez-Gonzalez , R. B. Barreiro , L. Toffolatti

We simulate the anisotropy in the cosmic microwave background (CMB) induced by cosmic strings. By numerically evolving a network of cosmic strings we generate full-sky CMB temperature anisotropy maps. Based on $192$ maps, we compute the…

天体物理学 · 物理学 2008-11-26 B. Allen , R. R. Caldwell , E. P. S. Shellard , A. Stebbins , S. Veeraraghavan

We propose a multi-scale edge-detection algorithm to search for the Gott-Kaiser-Stebbins imprints of a cosmic string (CS) network on the Cosmic Microwave Background (CMB) anisotropies. Curvelet decomposition and extended Canny algorithm are…

宇宙学与河外天体物理 · 物理学 2018-10-12 A. Vafaei Sadr , S. M. S. Movahed , M. Farhang , C. Ringeval , F. R. Bouchet

We use wavelet and curvelet transforms to extract signals of cosmic strings from cosmic microwave background (CMB) temperature anisotropy maps, and to study the limits on the cosmic string tension which various ongoing CMB temperature…

宇宙学与河外天体物理 · 物理学 2017-06-21 Lukas Hergt , Adam Amara , Robert Brandenberger , Tomasz Kacprzak , Alexandre Refregier

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

We study how the presence of world-sheet currents affects the evolution of cosmic string networks, and their impact on predictions for the cosmic microwave background (CMB) anisotropies generated by these networks. We provide a general…

宇宙学与河外天体物理 · 物理学 2020-10-21 I. Yu. Rybak , A. Avgoustidis , C. J. A. P. Martins

A new method for removing point radio sources and other non-Gaussian noise is proposed as a means of improving the accuracy of estimates of the angular power spectrum of the cosmic microwave background (CMB). The main idea of the method is…

天体物理学 · 物理学 2009-11-13 Anisa T. Bajkova

We describe a Bayesian framework for estimating the time-domain noise covariance of CMB observations, typically parametrized in terms of a 1/f frequency profile. This framework is based on the Gibbs sampling algorithm, which allows for…

天体物理仪器与方法 · 物理学 2015-05-30 I. K. Wehus , S. K. Næss , H. K. Eriksen

Un-doing the effect of gravitational lensing on the Cosmic Microwave Background (`de-lensing') is essential in shaping constraints on weak signals limited by lensing effects on the CMB, for example on a background of primordial…

宇宙学与河外天体物理 · 物理学 2025-10-24 Louis Legrand , Julien Carron

We study diffusion damping of acoustic waves in the photon-baryon fluid due to cosmic strings, and calculate the induced $\mu$- and $y$-type spectral distortions of the cosmic microwave background. For cosmic strings with tension within…

宇宙学与河外天体物理 · 物理学 2013-08-21 Hiroyuki Tashiro , Eray Sabancilar , Tanmay Vachaspati
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