The Daocheng site is one of the three candidate sites for the Large Optical/infrared Telescope (LOT) of China. It was discovered by Yunnan Observatories during the survey of potential sites for the next-generation large-aperture solar telescopes of China. This paper describes the overview of the site, the observation platform and the monitor instrument. In addition, simple statistical results are presented (from November, 2016 up to December, 2017). Detailed data results can refer to the overview of LOT site testing and data analysis articles, which were published during the same period.

Atmospheric turbulence reduces the image quality and resolution of ground-based optical telescopes. Future large solar telescopes (e.g. the CGST, China Giant Solar Telescope) should be equipped with adaptive optics (AO) systems. The design of AO systems is associated with atmospheric optical turbulence parameters, especially the profile of the refractive index structure $C_{n}^{2}(h)$. With the solar differential image motion monitor (S-DIMM) and the profiler of the moon limb (PML), a simplified version of a PML, termed a profiler of the differential solar limb (PDSL), was built in order to determine the daytime $C_{n}^{2}(h)$ and other atmospheric turbulence parameters. A PDSL with differential solar limb fluctuations was used to determine the turbulence profiling, and the extended solar limb extends the range of separation angles for a higher resolution of the height profile. The PDSL structure and its performance are described. In addition, numerical simulations were conducted to verify the effectiveness of the method. As revealed from the simulation results, the layered integral coefficient matrix is capable of solving the discretization error and enhancing the inversion accuracy of the turbulence contour. The first test results at Mt Wumingshan (a candidate site for the CGST) are presented.

Surface-layer turbulence, especially the turbulence close to the ground (ground-level, GL), critically determines the height at which to locate a ground-based telescope. It is also vital to assess the contribution of the GL to the total turbulence. To characterize the day-time turbulence at the GL at the Mt Wumingshan (Mt WMS) site (a candidate site for the Chinese next-generation large Solar Telescope), a microthermal sensor (MS) was installed to detect fluctuations of the temperature at the GL and estimate the contribution of the GL to the total turbulence. The MSs were placed at six levels on a 22-m-high tower to measure the refractive index |$C_{n}^{2}$| configuration constant. This study presents the day-time optical turbulences due to the GL at the Mt WMS site and compares them with the integrated day-time seeing that was obtained by the Wumingshan Mountain Automated Solar Differential Image Motion Monitor (WMA-SDIMM). MS and WMA-SDIMM data were obtained simultaneously for a total of 16 d during June to October 2017. The average r₀ of the GL was found to be |$r_{0}^{\rm gl}(\rm {1\, m,16\, m})=11.04\, {\rm cm}$| and |$r_{0}^{\rm gl}({\rm 16\,m,22\,m})=61.64\,{\rm cm}$|⁠. The contribution of the GL (8 to 22 m) to the total turbulence was |$13.05{{\ \rm per\ cent}}$| on average, complying with a |$8.0{{\ \rm per\ cent}}$| reduction of the total seeing. At the height of 22 m, most of the GL turbulence was produced below 16 m.

About ten years ago, we established the first coronagraph that has been continuously operating on the high plateau of western China. This coronagraph is an internal occulting, 10 cm aperture instrument, installed at Lijiang Station through a collaboration with the Norikura Station of the National Astronomical Observatory of Japan. To ensure high efficiency in current and future coronal observations, developing integrated observation systems is essential for reliable, autonomous, and remote operation of coronagraphs. This paper introduces an advanced integrated observation and control system, based on the Lijiang 10 cm coronagraph. The coronagraph focuses on the observations for the solar inner corona, capturing the coronal green-line emission within a field range from $1.03R_{⨀}$ to $2.5R_{⨀}$. To enhance the observational precision and efficiency, a comprehensive integrated system has been designed, incorporating various subsystems, including precise pointing and tracking mechanisms, a multi-band filter system, a protective dome system, and a robust data storage infrastructure. This paper details the hardware architecture and software frameworks supporting each subsystem. Results from extended operational testing confirm the stability of the system, its capacity for autonomous and remote observations, and significant improvements in the automation and efficiency of coronal imaging. The automated observation system will be further improved and used for our future coronagraphs to be developed for coronal magnetism diagnosis.