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arXiv · 1807.01371

The operational and control software of Multi-channel Antarctic Solar Telescope

Abstract

MARST (Multi-channel Antarctic Solar Telescope) aims to observe the Sun in multiple wavebands in Antarctica and will be China's first solar telescope in Antarctica. The telescope has two tubes, corresponding to Photosphere observation which uses 11 filters and Chromosphere observation in H{\alpha} waveband. The two tubes need to be coordinated to observe at the same time. The telescope will observe the Sun for a long time, so a self-guiding module is needed to improve sun tracking. Besides, performing solar specific flat-field exposure is necessary for analyzing. EPICS is introduced to control each hardware and an autonomous observation system based on RTS2 is designed under such demands. EPICS application modules are implemented for each device: telescope mount & focuser, filter wheel, H{\alpha} filter, dome with webcams, Andor CCD and PI CCD. We also integrate EPICS modules into RTS2 framework with an XML format configuration. To control these applications autonomously we have developed a RTS2 executor module where two plan classes are instantiated to control two sets of filters and CCDs, and to ensure only one could control the mount at the same time. Different types of observation plans are designed to describe different series of processes with different priorities. To improve sun tracking, we calculate the centroid of each image to get the offset, then apply the correction to the telescope during observation process. For frontend users, a GUI based on PyQt5 and QML is implemented and connects to rts2-httpd and rts2-proxy modules so that users can control devices, check images and get logs.

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Ya-qi Chen, Ming-hao Jia, Guang-yu Zhang, Zhi-yue Wang, Yi-ling Xu, Yi Feng, Jie Chen, Hong-fei Zhang, Peng Jiang, Tuo Ji, Jian Wang. 2018-06-20. The operational and control software of Multi-channel Antarctic Solar Telescope. https://arxiv.org/abs/1807.01371

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