Xin-Chun Hu1, Xiao-Hong Li1, Yan Wang1, Wen-Fan Feng1, Ming-Yue Zhou1, Yi-Ming Hu2,3, Shou-Cun Hu4,5, Jian-Wei Mei2,3 and Cheng-Gang Shao1
1 MOE Key Laboratory of Fundamental Physical Quantities Measurements, Hubei Key Laboratory of Gravitation and Quantum Physics, School of Physics, Huazhong University of Science and Technology, 1037 Luoyu Road, Wuhan 430074, China
2 TianQin Research Center for Gravitational Physics, Sun Yat-Sen University, Zhuhai 519082, China
3 School of Physics and Astronomy, Sun Yat-Sen University, Zhuhai 519082, China
4 Key Laboratory of Planetary Sciences, Purple Mountain Observatory, Chinese Academy of Sciences, 8 Yuanhua Road, Nanjing 210008, China
5 University of Chinese Academy of Sciences, Beijing 100049, China
Abstract. TianQin is a space-based laser interferometric gravitational wave detector aimed at detecting gravitational waves at low frequencies (0.1 mHz – 1 Hz). It is formed by three identical dragfree spacecrafts in an equilateral triangular constellation orbiting around the Earth. The distance between each pair of spacecrafts is approximately 1.7×105 km. The spacecrafts are interconnected by infrared laser beams forming up to three Michelson-type interferometers. The detailed mission design and the study of science objectives for the TianQin project depend crucially on the orbit and the response of the detector. In this paper, we provide the analytic expressions for the coordinates of the orbit for each spacecraft in the heliocentric-ecliptic coordinate system to the leading orders. This enables a sufficiently accurate study of science objectives and data analysis, and serves as a first step to further orbit design and optimization. We calculate the response of a single Michelson detector to plane gravitational waves in arbitrary waveform which is valid in the full range of the sensitive frequencies. It is then used to generate the more realistic sensitivity curve of TianQin. We apply this model on a reference white-dwarf binary as a proof of principle.
DOI: 10.1088/1361-6382/aab52f
