Cosmic Microwave Background temperature and polarization anisotropies from the large-N limit of global defects

Abstract

We determine the full C_l spectra and correlation functions of the temperature and polarization anisotropies in the CMB, generated by a source modeled by the large N limit of spontaneously broken global O(N)-theories. We point out a problem in the standard approach of treating the radiation-matter transition by interpolating the eigenvectors of the unequal-time correlators of the source energy-momentum tensor. This affects the CMB predictions from all type of cosmic defects. We propose a method to overcome this difficulty, and find that in the large-N global model that we study, differences in the final CMB power spectra amplitudes reach up to 25%, when compared to implementations of the eigenvector interpolation technique. We discuss as well how to optimally search for the contribution in the CMB from active sources such as cosmic defects, in experiments like Planck, COrE and PRISM.

16+4 pages, 13 figures (Version 2: minor changes to match published version in PRD)

References in corpus (9)

• The number of cosmic string loops
• Gravitational-Wave Stochastic Background from Kinks and Cusps on Cosmic Strings
• Gravitational Waves from Abelian Gauge Fields and Cosmic Strings at Preheating
• Exact Scale-Invariant Background of Gravitational Waves from Cosmic Defects
• A Nearly Scale Invariant Spectrum of Gravitational Radiation from Global Phase Transitions
• Cosmic microwave anisotropies from BPS semilocal strings
• The CMB temperature bispectrum induced by cosmic strings
• The local B-polarization of the CMB: a very sensitive probe of cosmic defects
• CMB anisotropies from acausal scaling seeds

Cited by in corpus (10)

• Gravitational wave background from Standard Model physics: Qualitative features
• New CMB constraints for Abelian Higgs cosmic strings
• Cosmic Microwave Background constraints for global strings and global monopoles
• Energy-momentum correlations for Abelian Higgs cosmic strings
• Can Self-Ordering Scalar Fields explain the BICEP2 B-mode signal?
• Probing early-universe phase transitions with CMB spectral distortions
• Reheating signature in the gravitational wave spectrum from self-ordering scalar fields
• Primordial magnetic fields from self-ordering scalar fields
• Weak lensing from self-ordering scalar fields
• Cosmic backgrounds from the radio to the far-infrared: recent results and perspectives from cosmological and astrophysical surveys