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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 want to find the cosmological constant influence on cosmic microwave background (CMB) temperature due to moving linear cosmic strings. Considering the space-time metric of a linear cosmic string in an accelerated expanding universe, the…

广义相对论与量子宇宙学 · 物理学 2016-01-20 S. Y. Rokni , H. Razmi , M. R. Bordbar

Using Monte Carlo simulations of perturbations induced by cosmic strings on the microwave background, we demonstrate the scale invariance of string fluctuation patterns. By comparing string-induced fluctuation patterns with gaussian random…

天体物理学 · 物理学 2009-10-28 Andrea M. Gilbert , Leandros Perivolaropoulos

Using an analytical model for the string network we show that the kurtosis of cosmic microwave background (CMB) temperature gradient maps is a good statistic to distinguish between the cosmic string model and inflationary models of…

天体物理学 · 物理学 2011-05-10 R. Moessner , L. Perivolaropoulos , R. Brandenberger

We use a convolutional neural network (CNN) to study cosmic string detection in cosmic microwave background (CMB) flat sky maps with Nambu-Goto strings. On noiseless maps we can measure string tensions down to order $10^{-9}$, however when…

宇宙学与河外天体物理 · 物理学 2021-06-03 Razvan Ciuca , Oscar F. Hernández

We perform a multiparameter likelihood analysis to compare measurements of the cosmic microwave background (CMB) power spectra with predictions from models involving cosmic strings. Adding strings to the standard case of a primordial…

天体物理学 · 物理学 2008-11-26 Neil Bevis , Mark Hindmarsh , Martin Kunz , Jon Urrestilla

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 investigate the cosmological information in higher-order statistics of the cosmic microwave background (CMB) lensing convergence field for a near-term experiment with noise properties similar to the Simons Observatory (SO). Using a fully…

宇宙学与河外天体物理 · 物理学 2026-03-16 Shu-Fan Chen , J. Colin Hill , Zoltán Haiman

We develop a method of constraining the cosmic string tension $G\mu$ which uses the Canny edge detection algorithm as a means of searching CMB temperature maps for the signature of the Kaiser-Stebbins effect. We test the potential of this…

天体物理学 · 物理学 2009-11-19 Andrew Stewart , Robert Brandenberger

By actively distorting the Cosmic Microwave Background (CMB) over our past light cone, cosmic strings are unavoidable sources of non-Gaussianity. Developing optimal estimators able to disambiguate a string signal from the primordial type of…

宇宙学与河外天体物理 · 物理学 2012-08-22 Christophe Ringeval , Francois R. Bouchet

The Cosmological Microwave Background (CMB) is of premier importance for the cosmologists to study the birth of our universe. Unfortunately, most CMB experiments such as COBE, WMAP or Planck do not provide a direct measure of the…

宇宙学与河外天体物理 · 物理学 2015-06-05 J. Bobin , J. -L. Starck , F. Sureau , S. Basak

We propose a new method for extracting the non-Gaussian signatures on the isotemperature statistics in the cosmic microwave background (CMB) sky, which is induced by the gravitational lensing due to the intervening large-scale structure of…

天体物理学 · 物理学 2009-11-06 Masahiro Takada

We compute the one-point probability distribution function of small-angle cosmic microwave background temperature fluctuations due to curved cosmic (super-)strings with a simple model of string network by performing Monte Carlo simulations.…

宇宙学与河外天体物理 · 物理学 2014-11-20 Daisuke Yamauchi , Yuuiti Sendouda , Chul-Moon Yoo , Keitaro Takahashi , Atsushi Naruko , Misao Sasaki

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

The breakdown of statistical homogeneity and isotropy of cosmic perturbations is a generic feature of ultra large scale structure of the cosmos, in particular, of non trivial cosmic topology. The statistical isotropy (SI) of the Cosmic…

天体物理学 · 物理学 2008-11-26 Tarun Souradeep , Amir Hajian

The Cosmic Microwave Background (CMB) fluctuations at very small angular scales (less than $10'$) induced by matter sources are computed in a simplified way. The result corrects a previous formula appearing in the literature. The small…

天体物理学 · 物理学 2011-05-10 Mark Hindmarsh

We describe an efficient and exact method that enables global Bayesian analysis of cosmic microwave background (CMB) data. The method reveals the joint posterior density (or likelihood for flat priors) of the power spectrum $C_\ell$ and the…

天体物理学 · 物理学 2009-11-10 Benjamin D. Wandelt , David L. Larson , Arun Lakshminarayanan

Contemporary cosmic microwave background (CMB) experiments typically have observing bands covering the range 20 - 800 GHz. Certain science goals, including the detection of $\mu$-type distortions to the CMB spectrum and the characterization…

宇宙学与河外天体物理 · 物理学 2024-06-07 David Zegeye , Thomas Crawford , Jens Chluba , Mathieu Remazeilles , Keith Grainge

I review recent progress towards a detailed understanding of the power spectrum of cosmic string perturbations induced on the Microwave Background (CMB). The use of a simple analytic model allows to include important effects that have not…

天体物理学 · 物理学 2007-05-23 Leandros Perivolaropoulos

Line discontinuities in cosmic microwave background anisotropy maps are a distinctive prediction of models with cosmic strings. These signatures are visible in anisotropy maps with good angular resolution and should be identifiable using…

天体物理学 · 物理学 2009-06-23 Stephen Amsel , Joshua Berger , Robert H. Brandenberger