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We explore the use of random forest and gradient boosting, two powerful tree-based machine learning algorithms, for the detection of cosmic strings in maps of the cosmic microwave background (CMB), through their unique Gott-Kaiser-Stebbins…

Cosmology and Nongalactic Astrophysics · Physics 2018-10-12 A. Vafaei Sadr , M. Farhang , S. M. S. Movahed , B. Bassett , M. Kunz

Anisotropies in the temperature of the cosmic microwave background have been detected on a range of scales by several different experiments. These anisotropies reflect the primordial spectrum of metric perturbations in the early universe.…

Astrophysics · Physics 2009-10-22 Scott Dodelson , Arthur Kosowsky

We reconsider the effect of electromagnetic radiation from superconducting strings on cosmic microwave background (CMB) mu- and y-distortions and derive present (COBE-FIRAS) and future (PIXIE) constraints on the string tension, mu_s, and…

Cosmology and Nongalactic Astrophysics · Physics 2012-12-18 Hiroyuki Tashiro , Eray Sabancilar , Tanmay Vachaspati

This work presents a detailed analysis of Cosmic Microwave Background (CMB) radiation intensity observations. The CMB is a relic of the Big Bang and its study greatly enhances our knowledge of cosmology. This work has led to new values for…

Astrophysics · Physics 2007-05-23 Henrik P. Nordberg , George F. Smoot

In this paper, we present results for large-angle CMB anisotropies generated from high resolution simulations of cosmic string networks in a range of flat FRW universes with a cosmological constant. Using an ensemble of all-sky maps, we…

Astrophysics · Physics 2008-11-26 M. Landriau , E. P. S. Shellard

We present a new analytical method to calculate the small angle CMB temperature angular power spectrum due to cosmic (super-)string segments. In particular, using our method, we clarify the dependence on the intercommuting probability $P$.…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-21 Daisuke Yamauchi , Keitaro Takahashi , Yuuiti Sendouda , Chul-Moon Yoo , Misao Sasaki

Cosmic strings formed during inflation are expected to be either diluted over super-Hubble distances, i.e., invisible today, or to have crossed our past light cone very recently. We discuss the latter situation in which a few strings…

Cosmology and Nongalactic Astrophysics · Physics 2016-03-09 Christophe Ringeval , Daisuke Yamauchi , Jun'ichi Yokoyama , Francois R. Bouchet

We re-examine the constraints on the cosmic string tension from Cosmic Microwave Background (CMB) and matter power spectra, and also from limits on a stochastic background of gravitational waves provided by pulsar timing. We discuss the…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 Richard Battye , Adam Moss

The Cosmic Microwave Background (CMB) bispectrum of the temperature anisotropies induced by a network of cosmic strings is derived for small angular scales, under the assumption that the principal cause of temperature fluctuations is the…

Cosmology and Nongalactic Astrophysics · Physics 2009-11-06 Mark Hindmarsh , Christophe Ringeval , Teruaki Suyama

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…

General Relativity and Quantum Cosmology · Physics 2016-01-20 S. Y. Rokni , H. Razmi , M. R. Bordbar

We examine the spectrum of gravitational radiation emitted by a network of cosmic strings, with emphasis on the observational constraints and the opportunities for detection. The analysis improves over past work, as we use a…

Astrophysics · Physics 2009-12-30 R. R. Caldwell , R. A. Battye , E. P. S. Shellard

Electromagnetic radiation from superconducting cosmic string loops can reionize neutral hydrogen in the universe at very early epochs, and affect the cosmic microwave background (CMB) temperature and polarization correlation functions at…

Cosmology and Nongalactic Astrophysics · Physics 2012-06-22 Hiroyuki Tashiro , Eray Sabancilar , Tanmay Vachaspati

We present in detail the convolutional neural network used in our previous work to detect cosmic strings in cosmic microwave background (CMB) temperature anisotropy maps. By training this neural network on numerically generated CMB…

Cosmology and Nongalactic Astrophysics · Physics 2019-03-15 Razvan Ciuca , Oscar F. Hernández , Michael Wolman

We present updated constraints on cosmic string and superstring parameters derived from Cosmic Microwave Background (CMB) anisotropies. The constraints are obtained via Markov Chain Monte Carlo (MCMC) analyses of the full \textit{Planck}…

Cosmology and Nongalactic Astrophysics · Physics 2026-03-23 Juhan Raidal , Anastasios Avgoustidis , Edmund Copeland , Adam Moss

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…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-14 Y. Wiaux , G. Puy , P. Vandergheynst

If they exist, networks of superconducting cosmic strings are capable of injecting copious amounts of electromagnetic energy into the background over a broad range of frequencies. We study this injection both analytically, as well as…

Cosmology and Nongalactic Astrophysics · Physics 2023-05-18 Bryce Cyr , Jens Chluba , Sandeep Kumar Acharya

We present the first ever calculation of cosmic microwave background CMB anisotropy power spectra from semilocal cosmic strings, obtained via simulations of a classical field theory. Semilocal strings are a type of non-topological defect…

Astrophysics · Physics 2009-06-23 Jon Urrestilla , Neil Bevis , Mark Hindmarsh , Martin Kunz , Andrew R. Liddle

The cosmic microwave background temperature is a cornerstone astrophysical observable. Its present value is tightly constrained, but its redshift dependence, which can now be determined until redshift $z\sim6.34$, is also an important probe…

Cosmology and Nongalactic Astrophysics · Physics 2022-11-23 L. Gelo , C. J. A. P. Martins , N. Quevedo , A. M. M. Vieira

A class of well-motivated models of inflation end by producing cosmic strings. The current status of efforts to calculate and observe the signals from such models are outlined, with a particular emphasis on cosmic strings, and on the Cosmic…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-28 Mark Hindmarsh

Weak gravitational lensing of the cosmic microwave background (CMB) carries imprints of the physics operating at redshifts much lower than that of recombination and serves as an important probe of cosmological structure formation, dark…

Cosmology and Nongalactic Astrophysics · Physics 2024-09-20 Victor C. Chan , Renée Hložek , Joel Meyers , Alexander van Engelen