The Solar Upper Transition Region Imager (SUTRI) Onboard the SATech-01 Satellite

• Published in: Research in astronomy and astrophysics Vol. 23; no. 6; pp. 65014 - 171
• Main Authors: Bai, Xianyong, Tian, Hui, Deng, Yuanyong, Wang, Zhanshan, Yang, Jianfeng, Zhang, Xiaofeng, Zhang, Yonghe, Qi, Runze, Wang, Nange, Gao, Yang, Yu, Jun, He, Chunling, Shen, Zhengxiang, Shen, Lun, Guo, Song, Hou, Zhenyong, Ji, Kaifan, Bi, Xingzi, Duan, Wei, Yang, Xiao, Lin, Jiaben, Hu, Ziyao, Song, Qian, Yang, Zihao, Chen, Yajie, Qiao, Weidong, Ge, Wei, Li, Fu, Jin, Lei, He, Jiawei, Chen, Xiaobo, Zhu, Xiaocheng, He, Junwang, Shi, Qi, Liu, Liu, Li, Jinsong, Xu, Dongxiao, Liu, Rui, Li, Taijie, Feng, Zhenggong, Wang, Yamin, Fan, Chengcheng, Liu, Shuo, Guo, Sifan, Sun, Zheng, Wu, Yuchuan, Li, Haiyu, Yang, Qi, Ye, Yuyang, Gu, Weichen, Wu, Jiali, Zhang, Zhe, Yu, Yue, Ye, Zeyi, Sheng, Pengfeng, Wang, Yifan, Li, Wenbin, Huang, Qiushi, Zhang, Zhong
• Format: Journal Article
• Language: English
• Published: Beijing National Astromonical Observatories, CAS and IOP Publishing 01.06.2023; IOP Publishing; National Astronomical Observatories,Chinese Academy of Sciences,Beijing 100101,China; School of Astronomy and Space Science,University of Chinese Academy of Sciences,Beijing 101408,China%School of Earth and Space Sciences,Peking University,Beijing 100871,China; Key Laboratory of Solar Activity and Space Weather,National Space Science Center,Chinese Academy of Sciences,Beijing 100190,China%Tongji University,Institute of Precision Optical Engineering,School of Physics Science and Engineering,Key Laboratory of Advanced Micro-Structured Materials MOE,Shanghai,China%Xi'an Institute of Optics and Precision Mechanics,Chinese Academy of Sciences,Xi'an 710119,China%Innovation Academy for Microsatellites,Chinese Academy of Sciences,Shanghai 201304,China%School of Earth and Space Sciences,Peking University,Beijing 100871,China%Yunnan Observatories,Chinese Academy of Sciences,Kunming,650011,China%National Astronomical Observatories,Chinese Academy of Sciences,Beijing 100101,China%School of Astronomy and Space Science,University of Chinese Academy of Sciences,Beijing 101408,China; School of Earth and Space Sciences,Peking University,Beijing 100871,China
• Subjects: Aerospace environments; Atmosphere; Corona; Coronal mass ejection; Data acquisition; Image acquisition; Image stabilizers; Line spectra; Lower atmosphere; Multilayers; Solar activity; Solar atmosphere; Solar images; space vehicles: instruments; Spatial resolution; Sun-synchronous orbits; Sun: activity; Sun: transition region; Sun: UV radiation; Temperature regime; Sun:UV radiation; Sun:transition region; space vehicles:instruments; Sun:activity
• ISSN: 1674-4527; 2397-6209
• DOI: 10.1088/1674-4527/accc74

The Solar Upper Transition Region Imager (SUTRI) onboard the Space Advanced Technology demonstration satellite (SATech-01), which was launched to a Sun-synchronous orbit at a height of ∼500 km in 2022 July, aims to test the on-orbit performance of our newly developed Sc/Si multi-layer reflecting mirror and the 2k×2k EUV CMOS imaging camera and to take full-disk solar images at the Ne vii 46.5 nm spectral line with a filter width of ∼3 nm. SUTRI employs a Ritchey–Chrétien optical system with an aperture of 18 cm. The on-orbit observations show that SUTRI images have a field of view of ∼ 41.′6 × 41.′6 and a moderate spatial resolution of ∼8″ without an image stabilization system. The normal cadence of SUTRI images is 30 s and the solar observation time is about 16 hr each day because the earth eclipse time accounts for about 1/3 of SATech-01's orbit period. Approximately 15 GB data is acquired each day and made available online after processing. SUTRI images are valuable as the Ne vii 46.5 nm line is formed at a temperature regime of ∼0.5 MK in the solar atmosphere, which has rarely been sampled by existing solar imagers. SUTRI observations will establish connections between structures in the lower solar atmosphere and corona, and advance our understanding of various types of solar activity such as flares, filament eruptions, coronal jets and coronal mass ejections.