Concepts and status of Chinese space gravitational wave detection projects

TL;DR

This paper reviews Chinese space-based gravitational wave observatories TianQin and Taiji, highlighting their unique designs, technological development milestones, and potential collaborations with other projects like LISA to enhance GW detection capabilities.

Contribution

It introduces the concepts, development milestones, and collaborative prospects of TianQin and Taiji, expanding the landscape of space-based gravitational wave detection.

Findings

TianQin has a geocentric orbit with higher frequency sensitivity.

Taiji's design is similar to LISA but with longer arm length and higher sensitivity.

All three projects aim to operate concurrently in the 2030s, enabling collaborative GW source analysis.

Abstract

Gravitational wave (GW) detection in space probes GW spectrum that is inaccessible from the Earth. In addition to LISA project led by European Space Agency, and the DECIGO detector proposed by the Japan Aerospace Exploration Agency, two Chinese space-based GW observatories -- TianQin and Taiji -- are planned to be launched in the 2030s. TianQin has a unique concept in its design with a geocentric orbit. Taiji's design is similar to LISA, but is more ambitious with longer arm distance. Both facilities are complementary to LISA, considering that TianQin is sensitive to higher frequencies and Taiji probes similar frequencies but with higher sensitivity. In this Perspective we explain the concepts for both facilities and introduce the development milestones of TianQin and Taiji projects in testing extraordinary technologies to pave the way for future space-based GW detections. Considering that LISA, TianQin and Taiji have similar scientific goals, all are scheduled to be launched around the 2030s and will operate concurrently, we discuss possible collaborations among them to improve GW source localization and characterization.