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We present the first complete Markov chain Monte Carlo analysis of cosmological models with evolving cosmic (super)string networks, using the unconnected segment model in the unequal-time correlator formalism. For ordinary cosmic string…

Cosmology and Nongalactic Astrophysics · Physics 2016-06-08 Tom Charnock , Anastasios Avgoustidis , Edmund J. Copeland , Adam Moss

We find the constraints from WMAP and SDSS data on the fraction of cosmological fluctuations sourced by local cosmic strings using a Markov Chain Monte Carlo (MCMC) analysis. In addition to varying the usual 6 cosmological parameters and…

Astrophysics · Physics 2014-10-13 Mark Wyman , Levon Pogosian , Ira Wasserman

We calculate a signature of cosmic strings in the polarization of the cosmic microwave background (CMB). We find that ionization in the wakes behind moving strings gives rise to extra polarization in a set of rectangular patches in the sky…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 Rebecca J. Danos , Robert H. Brandenberger , Gil Holder

Recent data from the WMAP, ACT and SPT experiments provide precise measurements of the cosmic microwave background temperature power spectrum over a wide range of angular scales. The combination of these observations is well fit by the…

The recombination history of the Universe depends exponentially on the temperature, T_0, of the cosmic microwave background. Therefore tiny changes of T_0 are expected to lead to significant changes in the free electron fraction. Here we…

Astrophysics · Physics 2009-11-13 J. Chluba , R. A. Sunyaev

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…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 E. Jeong , Carlo Baccigalupi , G. F. Smoot

We study the effect of weak lensing by cosmic (super-)strings on the anisotropies of cosmic microwave background (CMB). In developing a method to calculate the lensing convergence field due to strings, and thereby temperature and…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-19 Daisuke Yamauchi , Keitaro Takahashi , Yuuiti Sendouda , Chul-Moon Yoo

We derive a general procedure for calculating the gravitational wave background (GWB) from cosmic string loops whose typical shape evolves over time, as in gravitational backreaction. Using the results of a large-scale study of numerical…

General Relativity and Quantum Cosmology · Physics 2026-03-26 Jeremy M. Wachter , Ken D. Olum , Jose J. Blanco-Pillado

We introduce a simple yet powerful {\it analytic} method which obtains the structure of cosmic microwave background anisotropies to better than 5-10\% in temperature fluctuations on {\it all} scales. It is applicable to {\it any} model in…

Astrophysics · Physics 2009-07-17 Wayne Hu , Naoshi Sugiyama

During cosmic recombination, charged particles bind into neutral atoms and the mean free path of photons rapidly increases, resulting in the familiar diffusion damping of primordial radiation temperature variations. An additional effect is…

Cosmology and Nongalactic Astrophysics · Physics 2023-10-04 Nathaniel Starkman , Glenn Starkman , Arthur Kosowsky

Making use of the wealth of new observational data coming from the sky it is possible to constrain particle physics theories beyond the Standard Model. One way to do this is illustrated in this article: a subset of theories admits cosmic…

Cosmology and Nongalactic Astrophysics · Physics 2014-01-21 Robert H. Brandenberger

Empirical estimates of the band power covariance matrix are commonly used in cosmic microwave background (CMB) power spectrum analyses. While this approach easily captures correlations in the data, noise in the resulting covariance estimate…

Cosmology and Nongalactic Astrophysics · Physics 2022-03-14 L. Balkenhol , C. L. Reichardt

We provide an analytical expression for the trispectrum of the Cosmic Microwave Background (CMB) temperature anisotropies induced by cosmic strings. Our result is derived for the small angular scales under the assumption that the…

Cosmology and Nongalactic Astrophysics · Physics 2010-04-06 Mark Hindmarsh , Christophe Ringeval , Teruaki Suyama

We perform the stastistics of temperature maxima and minima in COBE-DMR 2-year maps. For power-law spectra the surface distribution of peaks implies an amplitude consistent with more conventional analyses of COBE data (for instance, we get…

Astrophysics · Physics 2011-05-10 R. Fabbri , S. Torres

The redshift dependence of the cosmic microwave background temperature, $T(z)=T_0(1+z)$, is a key prediction of standard cosmology, but this relation is violated in many extensions thereof. Current astrophysical facilities can probe it in…

Cosmology and Nongalactic Astrophysics · Physics 2024-04-09 C. J. A. P. Martins , A. M. M. Vieira

Searches for primordial gravitational waves have resulted in constraints in a large frequency range from a variety of sources. The standard Cosmic Microwave Background (CMB) technique is to parameterise the tensor power spectrum in terms of…

Cosmology and Nongalactic Astrophysics · Physics 2020-10-14 Thomas J. Clarke , Edmund J. Copeland , Adam Moss

We introduce a new technique to detect the discrete temperature steps that cosmic strings might have left in the cosmic microwave background (CMB) anisotropy map. The technique provides a validity test on the pattern search of cosmic…

Astrophysics · Physics 2009-11-11 E. Jeong , G. F. Smoot

The problem of separation of different signals in the Cosmic Microwave Background (CMB) radiation using the difference in their statistics is analyzed. Considering samples of sequences which model the CMB as a superposition of signals, we…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 S. Mirzoyan , E. Poghosian

We show how observations of temperature fluctuations in cosmic microwave background (CMB) can be used to extract information related to the large scale structure, including dark matter distribution, pressure and halo velocities involving…

Astrophysics · Physics 2007-05-23 Asantha Cooray

Cosmic strings are predicted in many models beyond the Standard Model of particle physics. In models which admit strings, a network of strings will inevitably be formed in a phase transition in the early universe and will persist to the…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 Robert H. Brandenberger
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