The TianQin project: Current progress on science and technology
Jianwei Mei, Yanzheng Bai, Jiahui Bao, Enrico Barausse, Lin Cai, Enrico Canuto, Bin Cao, Weiming Chen, Yu Chen, Yanwei Ding, Hui‐Zong Duan, Hui-Min Fan, Wen-Fan Feng, Honglin Fu, Qing Gao, TianQuan Gao, Yungui Gong, Xingyu Gou, Chao-Zheng Gu, Defeng Gu, Zi-Qi He, M. Hendry, Wei Hong, Xin-Chun Hu, Yi-Ming Hu, Yuexin Hu, S. Huang, Xiangqing Huang, Qinghua Jiang, Yuan‐Ze Jiang, Y. Jiang, Zhen Jiang, Hongming Jin, Valeriya Korol, Hongyin Li, Ming Li, Ming Li, Peng-Cheng Li, Rongwang Li, Yuqiang Li, Zhu Li, Zhulian Li, Zhuxi Li, Yurong Liang, Zheng-Cheng Liang, Fang-Jie Liao, Qi Liu, Shuai Liu, Yan-Chong Liu, Li Liu, Peibo Liu, Xuhui Liu, Yuan Liu, Xiong-Fei Lu, Yang Lu, Z. H. Lu, Yan Luo, Zhicai Luo, V. K. Milyukov, Min Ming, Xiaoyu Pi, Cheng-Gang Qin, Shaobo Qu, Alberto Sesana, Cheng-Gang Shao, Changfu Shi, Wei Su, Ding-Yin Tan, Yu-Jie Tan, Zhuangbin Tan, Liangcheng Tu, Bin Wang, Chengrui Wang, Fengbin Wang, Guanfang Wang, Hai-Tian Wang, Jian Wang, Lijiao Wang, Panpan Wang, Xudong Wang, Yan Wang, Yifan Wang, Ran Wei, Shuchao Wu, Chunyu Xiao, Xiao-Shi Xu, Chao Xue, Fangchao Yang, Liang Yang, Ming-Lin Yang, Shan-Qing Yang, Bobing Ye, Hsien‐Chi Yeh, Shenghua Yu, Dongsheng Zhai, Caishi Zhang, Haitao Zhang, Jian-dong Zhang, Jie Zhang, Lihua Zhang
Abstract
Abstract TianQin is a planned space-based gravitational wave (GW) observatory consisting of three Earth-orbiting satellites with an orbital radius of about $10^5 \, {\rm km}$. The satellites will form an equilateral triangle constellation the plane of which is nearly perpendicular to the ecliptic plane. TianQin aims to detect GWs between $10^{-4} \, {\rm Hz}$ and $1 \, {\rm Hz}$ that can be generated by a wide variety of important astrophysical and cosmological sources, including the inspiral of Galactic ultra-compact binaries, the inspiral of stellar-mass black hole binaries, extreme mass ratio inspirals, the merger of massive black hole binaries, and possibly the energetic processes in the very early universe and exotic sources such as cosmic strings. In order to start science operations around 2035, a roadmap called the 0123 plan is being used to bring the key technologies of TianQin to maturity, supported by the construction of a series of research facilities on the ground. Two major projects of the 0123 plan are being carried out. In this process, the team has created a new-generation $17 \, {\rm cm}$ single-body hollow corner-cube retro-reflector which was launched with the QueQiao satellite on 21 May 2018; a new laser-ranging station equipped with a $1.2 \, {\rm m}$ telescope has been constructed and the station has successfully ranged to all five retro-reflectors on the Moon; and the TianQin-1 experimental satellite was launched on 20 December 2019—the first-round result shows that the satellite has exceeded all of its mission requirements.