Forecast constraints on cosmic strings from future CMB, pulsar timing and gravitational wave direct detection experiments

TL;DR

This paper evaluates how future gravitational wave, pulsar timing, and CMB experiments can constrain cosmic string properties, demonstrating that combined observations significantly improve parameter estimation accuracy.

Contribution

It introduces a comprehensive Fisher matrix analysis of upcoming experiments to constrain cosmic string parameters, highlighting the benefits of multi-probe data integration.

Findings

Combined observations break parameter degeneracies.

Future space-borne interferometers offer precise parameter constraints.

Multiple observational methods enhance detection prospects.

Abstract

We study future observational constraints on cosmic string parameters from various types of next-generation experiments: direct detection of gravitational waves (GWs), pulsar timing array, and the cosmic microwave background (CMB). We consider both GW burst and stochastic GW background searches by ground- and space-based interferometers as well as GW background detection in pulsar timing experiments. We also consider cosmic string contributions to the CMB temperature and polarization anisotropies. These different types of observations offer independent probes of cosmic strings and may enable us to investigate cosmic string properties if the signature is detected. In this paper, we evaluate the power of future experiments to constrain cosmic string parameters, such as the string tension Gmu, the initial loop size alpha, and the reconnection probability p, by performing Fisher information matrix calculations. We find that combining the information from the different types of observations breaks parameter degeneracies and provides more stringent constraints on the parameters. We also find future space-borne interferometers independently provide a highly precise determination of the parameters.