Observational constraints on light cosmic strings from photometry and pulsar timing

TL;DR

This paper uses photometry and pulsar timing data to set constraints on the density of light cosmic strings, with pulsar timing providing the most stringent current limits and future telescopes promising significant improvements.

Contribution

It introduces observational constraints on light cosmic strings across a wide tension range using multiple data sources, highlighting pulsar timing's effectiveness.

Findings

Pulsar timing constrains cosmic string abundance to ^{-3}.

Current data exclude certain string densities in the tension range.

Future telescopes like SKA will significantly tighten these constraints.

Abstract

We constrain the cosmological density of cosmic string loops using two observational signatures -- gravitational microlensing and the Kaiser-Stebbins effect. Photometry from RXTE and CoRoT space missions and pulsar timing from Parkes Pulsar Timing Array, Arecibo and Green Bank radio telescopes allow us to probe cosmic strings in a wide range of tensions $G\mu/c^2=10^{-16}\div10^{-10}$. We find that pulsar timing data provide the most stringent constraints on the abundance of light strings at the level $\Omega_s \sim 10^{-3}$. Future observational facilities such as the Square Kilometer Array will allow one to improve these constraints by orders of magnitude.