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arXiv · 1908.11027

Development of image motion compensation system for 1.3 m telescope at Vainu Bappu Observatory

Sreekanth Reddy V·Ravinder Kumar Banyal·Sridharan R·P U Kamath·Aishwarya Selvaraj
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Abstract

We developed a tip-tilt system to compensate the turbulence induced image motion for 1.3 m telescope at Vainu Bappu Observatory, Kavalur. The instrument is designed to operate at visible wavelength band (480-700 nm) with a field of view $1^{\prime}\times1^{\prime}$. The tilt corrected images have shown up to $\approx$ 57% improvement in image resolution and a corresponding peak intensity increase by a factor of $\approx$ 2.8. A closed-loop correction bandwidth of $\approx$ 26 Hz has been achieved with on-sky tests and the root mean square motion of the star image has been reduced by a factor of $\sim$ 14. These results are consistent with theoretical and numerical predictions of wave-front aberrations caused by atmospheric turbulence and image quality improvement expected from a real-time control system. In this paper, we present the details of the instrument design, laboratory calibration studies and quantify its performance on the telescope.

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Sreekanth Reddy V, Ravinder Kumar Banyal, Sridharan R, P U Kamath, Aishwarya Selvaraj. 2019-08-29. Development of image motion compensation system for 1.3 m telescope at Vainu Bappu Observatory. https://arxiv.org/abs/1908.11027

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