# Ionization from Cosmic Strings at Cosmic Dawn

## TL;DR

This paper investigates how cosmic strings could ionize neutral hydrogen during the early universe, potentially leading to observable effects and new constraints on string properties and primordial magnetic fields.

## Contribution

It introduces a novel mechanism by which cosmic strings influence hydrogen ionization, linking string tension and magnetic fields to observable cosmic signals.

## Key findings

- Cosmic strings can significantly ionize hydrogen during cosmic dawn.
- Ionization effects depend on string tension and primordial magnetic field strength.
- Potential for new observational constraints on cosmic string parameters.

## Abstract

Cosmic strings produce charged particles which, by emitting electromagnetic radiation, partially ionize neutral hydrogen during the dark ages. Corrections to the ionization fraction of neutral hydrogen induced by cosmic strings could lead to new observational effects and/or new constraints on the string tension around $G\mu \sim 10^{-16} - 10^{-22}$ for values of the primordial magnetic field in the range $B_0 \sim 10^{-11}-10^{-9}$ Gauss.