Recently, the team of California State University Northridge (CSUN) and Nanjing Institute of Astronomical Optics and Technology (NIAOT) successfully tested a set of portable solar adaptive optics (PSAO) on NSO 0.8-meter Dunn telescope, and the results show our PSAO works very well for both wide-field and high-resolution correction. On August 16, 2014, we observed the Sunspot 2139 at near infrared J band (1.3um) under the seeing condition close to 1”. A FOV of 40”x 40” was used for wave-front sensing, such a FOV can cover the entire active region of a large sunspot, which is very important for solar physics research. As shown in the video below, the inner local structures and the granules around Sunspot 2139 are both clear to be seem after correction.
Comparing to other adaptive optics, PSAO features in compact size and low cost, it is suitable for connecting with different telescope platform as visiting instrument. To achieve the wide field and high resolution imaging, the wave-front sensing in adaptive optics faces great challenge in real-time wave-front calculation and measurement accuracy. PSAO has well solved the above problems, and provides the top-level quality of solar imaging. Doug Gilliam, the senior telescope and adaptive optics expert in NSO, commented our PSAO as a definitely competitive system. CSUN and the exoplanet imaging group in NIAOT have long-term collaboration in PSAO, this system had verified workable in the on-site test on Kitt Peak 1.6-m McMP telescope, but only a FOV of 10”x10” was corrected. It is the first time PSAO achieves wide field and high resolution imaging in the on-site test in August 2014. The PSAO currently uses 9x9 subapertures for wave-front sensing and reaches the open-loop frequency of 900Hz. We will report more updates for PSAO and release better results in future.
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