分类: 天文学 >> 天文仪器与技术 提交时间: 2024-07-31 合作期刊: 《天文技术与仪器(英文)》
摘要:The impact of structural stiffness on optical axis deviation poses a significant challenge in the design of equatorial telescope structures. A comprehensive analysis during the design process can reduce the reliance of a telescope on advanced control technologies, thereby improving its economic feasibility. Although full-system finite element analyses are reliable, they are encumbered by significant time requirements and limitations in covering all possible telescope orientations. Therefore, we propose an efficient and comprehensive analytical method to evaluate the optical axis deviation of equatorial telescopes across a full range of angles. To address the challenge of ensuring that the analysis covers all possible positions of an equatorial telescope, based on a model from SiTian project, we analyze the optical axis deviations caused by the fork arm at 25 different angles and then use fitting methods to obtain results for all angles. Based on the analysis results of the optical axis deviation caused by the stiffness of the optical tube in the horizontal position, we derive the results for the tube at any position using geometric relationships. Finally, we calculate the coupling factors and combine these impacts. Furthermore, we identify six discrete feature points to reflect possible telescope orientations and conduct comprehensive finite element analyses. The results are in alignment with those acquired through a comprehensive computational approach.
分类: 天文学 >> 天文仪器与技术 提交时间: 2024-06-06 合作期刊: 《天文技术与仪器(英文)》
摘要:With the growing significance of space weather forecasting, multi-layer magnetic and helioseismic telescopes are emerging as a key area of research. However, owing to the diverse operational processes and sophisticated hardware configurations of these devices, there is an urgent need for efficient autonomous observation capabilities. An autonomous Master Control System (MCS) can ensure efficient performance, data consistency, and stability, and the prototype presented here adopts a microservices architecture, breaking down the hardware into multiple subsystems and converting their functions into individual services. A central decision-making system leads the operations, supported by three auxiliary systems and three device control systems. Through inter-subsystem service calls, it achieves rapid imaging and spectroscopic monitoring. To verify system stability and observation efficiency, the system was tested on the Solar Full-disk Multi-layer Magnetograph. Experimental results verify this system can operate automatically for 4 consecutive months, acquire photospheric vector magnetic and Doppler velocity fields within a 15-minute interval, and measure chromospheric longitudinal magnetic and Doppler velocity fields in under 180 s. This ensures consistent and stable solar monitoring and serves as a practical methodological benchmark for the development of similar devices.
分类: 天文学 >> 天文仪器与技术 提交时间: 2025-06-03 合作期刊: 《Astronomical Techniques and Instruments》
摘要: This paper presents a comprehensive analysis of the photometric system of the University of Chinese Academy of Sciences 70 cm Telescope located at the Yan-qi Lake campus of the University of Chinese Academy of Sciences. We evaluated the linearity, bias stability, and dark current of the camera. Utilizing the Johnson-Cousins Blue-Visible-Red-Infrared filter system and an Andor DZ936 charge-coupled device camera, we conducted extensive observations of Landolt standard stars to determine the color terms, atmospheric extinction coefficients, photometric zero-points, and the sky background brightness. The results indicate that this telescope demonstrates excellent performance in photometric calibration and good system performance overall, meeting the requirements for limited scientific research and teaching purposes.
分类: 天文学 >> 天文仪器与技术 分类: 光学 >> 仪器仪表、测量和计量 分类: 光学 >> 相干和统计光学 提交时间: 2023-06-28
摘要: Co-phase and co-focus detection is one of the key technologies for large-aperture segmented mirror telescopes. In this paper, a new edge sensor based on fringes of equal thickness is developed, which can detect each segment's relative piston, tilt, and tip errors from the interferograms. Based on the co-focus demand for many ground-based seeing limited segmented mirror telescopes, an edge sensor prototype based on such a principle is built and applied in the indoor segmented mirror experiment system in the lab. According to the co-focus requirement of the Large Sky Area Multi-Object Fiber Spectroscopic Telescope, many simulations and experiments are carried out for co-focus error detection of the segmented mirror system. Experiment results show that the co-focus accuracy is better than 0.02 rms, which can meet the co-focus requirements of most large or extremely large segmented mirror astronomical telescopes.
分类: 天文学 >> 天文仪器与技术 提交时间: 2024-02-07 合作期刊: 《天文技术与仪器(英文)》
摘要:The Jiao Tong University Spectroscopic Telescope (JUST) is a 4.4-meter f/6.0 segmented-mirror telescope dedicated to spectroscopic observations. The JUST primary mirror is composed of 18 hexagonal segments, each with a diameter of 1.1 m. JUST provides two Nasmyth platforms for placing science instruments. One Nasmyth focus fits a field of view of 10 ′ and the other has an extended field of view of 1.2° with correction optics. A tertiary mirror is used to switch between the two Nasmyth foci. JUST will be installed at a site at Lenghu in Qinghai Province, China, and will conduct spectroscopic observations with three types of instruments to explore the dark universe, trace the dynamic universe, and search for exoplanets: (1) a multi-fiber (2000 fibers) medium-resolution spectrometer (R=4 000−5 000) to spectroscopically map galaxies and large-scale structure; (2) an integral field unit (IFU) array of 500 optical fibers and/or a long-slit spectrograph dedicated to fast follow-ups of transient sources for multi-messenger astronomy; (3) a high-resolution spectrometer (R~100 000) designed to identify Jupiter analogs and Earth-like planets, with the capability to characterize the atmospheres of hot exoplanets.