Probing the gravitational wave background from cosmic strings with Alternative LISA-TAIJI network

TL;DR

This paper assesses the potential of the LISA-TAIJI space detector network to detect the stochastic gravitational wave background from cosmic string loops, highlighting the optimal configuration for constraining cosmic string tension.

Contribution

It introduces and evaluates different configurations of the LISA-TAIJI network for detecting the SGWB from cosmic strings, demonstrating improved sensitivity over individual detectors.

Findings

LISA-TAIJIc has the best sensitivity among configurations.

The network can constrain cosmic string tension to Gμ=O(10^{-17}).

Joint detectors outperform individual detectors in SGWB detection.

Abstract

As one of the detection targets of all gravitational wave detectors at present, stochastic gravitational wave background (SGWB) provides us an important way to understand the evolution of our universe. In this paper, we explore the feasibility of detecting the SGWB generated by the loops, which arose throughout the cosmological evolution of the cosmic string network, by individual space detectors (e.g.~LISA, TAIJI) and joint space detectors (LISA-TAIJI). For joint detectors, we choose three different configurations of TAIJI (e.g.~TAIJIm, TAIJIp, TAIJIc) to form the LISA-TAIJI networks. And we investigate the performance of them to detect the SGWB. Though comparing the power-law sensitivity (PLS) curves of individual space detectors and joint detectors with energy density spectrum of SGWB. We find that LISA-TAIJIc has the best sensitivity for detecting the SGWB from cosmic string loops and is promising to further constrains the tension of cosmic sting $G\mu=O(10^{-17})$.