China's self-developed Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST) can observe 4000 target sources simultaneously. As of March 2019, the LAMOST team has released 11.25 million sets of spectral data (DR6), of which 9.37 million had a high signal-to-noise ratio (S/N>10), as well as the world’s largest stellar catalogue to date (6.36 million entries).

The Chinese Space Station Optical Survey Telescope (CSST) will be launched in 2024. With a wavelength coverage of 255 to 1000 nm, it is expected to obtain photometric data for billions of stars and spectroscopic data for hundreds of millions of stars over the course of a 10-year survey. The high spatial resolution and deep survey depth of this instrument will allow us to resolve individual stars in hundreds of nearby galaxies, such as Andromeda and Triangulum.

Our group is currently attempting to conduct a full census of binary systems in the LAMOST data, paying special attention to the binarity rate, orbital period and mass ratio distributions, and their dependence on the metallicities and spectral types of the components stars and host populations. We expect our efforts to yield clues on the early-phase evolution of binary systems, in addition to providing more detailed input for binary population synthesis studies. It should also be helpful for preliminary work fleshing out the details of the science goals of CSST.