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Experimental Astronomy

, Volume 45, Issue 1, pp 57–79 | Cite as

Development of a Lunar Scintillometer as part of the national large optical telescope site survey

  • Avinash Surendran
  • Padmakar S. Parihar
  • Ravinder K. Banyal
  • Anusha Kalyaan
Original Article

Abstract

Ground layer turbulence is a very important site characterization parameter used to assess the quality of an astronomical site. The Lunar Scintillometer is a simple and effective site-testing device for measuring the ground layer turbulence. It consists of a linear array of photodiodes which are sensitive to the slight variations in the moon’s brightness due to scintillation by the lower layers of the Earth’s atmosphere. The covariance of intensity values between the non-redundant photodiode baselines can be used to measure the turbulence profile from the ground up to a height determined by the furthest pair of detectors. The six channel lunar scintillometer that has been developed at the Indian Institute of Astrophysics is based closely on an instrument built by the team led by Andrei Tokovinin of Cerro Tololo Inter-American Observatory (CTIO), Chile (Tokovinin et al., Mon. Not. R. Astron. Soc. 404(3), 1186–1196 2010). We have fabricated the instrument based on the existing electronic design, and have worked on the noise analysis, an EMI (Electromagnetic Induction) resistant PCB design and the software pipeline for analyzing the data from the same. The results from the instrument’s multi-year campaign at Mount Saraswati, Hanle is also presented.

Keywords

Site survey Atmospheric turbulence Ground-layer seeing 

Notes

Acknowledgements

The authors would like to thank Prof. Andrei Tokovinin for his valuable correspondence and advice. We would like to thank the staff at IAO-Hanle, notably Mr. Dorje Angchuk and Mr. Sonam Jorphali. We would also like to thank Mr. Urgyan Dorjey, Mr. Dadul and Mr. Phunchok Angchok for the endless nights spent in monitoring the working of the instrument and the prompt despatch of data from the site. We are thankful to the staff at the IIA mechanical workshop including Mr. P.M.M. Kemkar and Mr. Periyanayagam for the mechanical design and fabrication of the instrument and the LX200 piggyback mount. We are also thankful to the Indian Institute of Astrophysics and the Department of Science and Technology for funding this project.

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Copyright information

© Springer Science+Business Media B.V., part of Springer Nature 2018

Authors and Affiliations

  1. 1.Indian Institute of AstrophysicsBangaloreIndia
  2. 2.School of Earth and Space ExplorationArizona State UniversityTempeUSA

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