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相关论文: Bounds on Cosmic Strings from WMAP and SDSS

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The predictions of the inflationary LCDM paradigm match today's high-precision measurements of the cosmic microwave background anisotropy extremely well. The same data put tight limits on other sources of anisotropy. Cosmic strings are a…

宇宙学与河外天体物理 · 物理学 2013-05-29 Cora Dvorkin , Mark Wyman , Wayne Hu

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…

天体物理学 · 物理学 2009-06-23 Jon Urrestilla , Neil Bevis , Mark Hindmarsh , Martin Kunz , Andrew R. Liddle

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}…

宇宙学与河外天体物理 · 物理学 2026-03-23 Juhan Raidal , Anastasios Avgoustidis , Edmund Copeland , Adam Moss

Cosmic string networks generate cosmological perturbations actively throughout the history of the universe. Thus, the string sourced anisotropy of the cosmic microwave background is not affected by Silk damping as much as the anisotropy…

天体物理学 · 物理学 2010-04-15 Levon Pogosian , S. -H. Henry Tye , Ira Wasserman , Mark Wyman

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 have searched the 1st-year WMAP W-Band CMB anisotropy map for evidence of cosmic strings. We have set a limit of $\delta = 8 \pi G \mu / c^2 < 8.2 \times 10^{-6}$ at 95% CL for statistical search for a significant number of strings in…

天体物理学 · 物理学 2009-11-10 E. Jeong , G. F. Smoot

We compare the anisotropies in the cosmic microwave background radiation measured by the COBE experiment to the predictions of cosmic strings. We use an analytic model for the $\Delta T/T$ power spectrum that is based on our previous…

高能物理 - 唯象学 · 物理学 2009-10-22 David P. Bennett , Albert Stebbins , Francois R. Bouchet

We investigate the effect of wiggly cosmic strings on the cosmic microwave background radiation anisotropy and matter power spectrum by modifying the string network model used by Albrecht et al.. We employ the wiggly equation of state for…

天体物理学 · 物理学 2016-08-25 Levon Pogosian , Tanmay Vachaspati

We present a significant update of the constraints on the Abelian Higgs cosmic string tension by cosmic microwave background (CMB) data, enabled both by the use of new high-resolution CMB data from suborbital experiments as well as the…

宇宙学与河外天体物理 · 物理学 2015-05-30 J. Urrestilla , N. Bevis , M. Hindmarsh , M. Kunz

We report a search for signatures of cosmic strings in the the Cosmic Microwave Background data from the Wilkinson Microwave Anisotropy Probe. We used a digital filter designed to search for individual cosmic strings and found no evidence…

天体物理学 · 物理学 2007-05-23 Amy S. Lo , Edward L. Wright

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

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 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…

天体物理学 · 物理学 2009-11-11 E. Jeong , G. F. Smoot

In a recent publication, we used the data from WMAP and SDSS to constrain the primordial perturbations and to predict the B-mode polarization sourced by cosmic string networks. We have been alerted by A. Slosar to the existence of errors in…

天体物理学 · 物理学 2007-05-23 Levon Pogosian , Ira Wasserman , Mark Wyman

We investigate cosmological evolution and implications of cosmic strings with time-dependent tension. We derive basic equations of time development of the correlation length and the velocity of such strings, based on the one scale model.…

高能物理 - 唯象学 · 物理学 2008-11-26 Kazuhide Ichikawa , Tomo Takahashi , Masahide Yamaguchi

Recent measurements of the cosmic microwave background (CMB) anisotropies by BOOMERANG and MAXIMA collaborations have tightened the observational constraints on theories of structure formation. They disagree with the predictions of…

天体物理学 · 物理学 2009-10-31 Levon Pogosian

We demonstrate that string motivated inflation ending via tachyonic instability leaves a detectable imprint on the cosmic microwave background (CMB) radiation by virtue of the excitation of non-Gaussian gravitational fluctuations. The…

高能物理 - 理论 · 物理学 2007-05-23 Kari Enqvist , Asko Jokinen , Anupam Mazumdar , Tuomas Multamaki , Antti Vaihkonen

We devise a measure n(r) to quantify a robust feature in the coherent cosmic perturbations, namely the narrowness of the first peak in the power spectrum of the Cosmic Microwave Background (CMB) anisotropy. A maximum-likelihood analysis…

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

We present cosmic microwave background (CMB) power spectra from recent numerical simulations of cosmic strings in the Abelian Higgs model and compare them to CMB power spectra measured by Planck. We obtain revised constraints on the cosmic…

宇宙学与河外天体物理 · 物理学 2017-02-28 Joanes Lizarraga , Jon Urrestilla , David Daverio , Mark Hindmarsh , Martin Kunz

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…

天体物理学 · 物理学 2008-11-26 M. Landriau , E. P. S. Shellard
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