Constraints on Superconducting Cosmic Strings from Early Reionization

TL;DR

This paper investigates how electromagnetic emissions from superconducting cosmic strings could have caused early universe reionization and affected the CMB, providing new constraints on string properties using WMAP7 data.

Contribution

It introduces constraints on the tension and current of superconducting cosmic strings based on their impact on early reionization and CMB observations, improving previous spectral distortion limits.

Findings

String current must be less than 10^7 GeV for a wide tension range.

Electromagnetic radiation from strings can significantly influence early reionization.

Constraints are derived from WMAP7 data, refining earlier bounds.

Abstract

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 large angular scales. We constrain the string tension and current using WMAP7 data, and compare with earlier constraints that employed CMB spectral distortions. Over a wide range of string tensions, the current on the string has to be less than 10^7 GeV.