AI Article Synopsis
- The study focuses on how optical turbulence impacts the performance of astronomical telescopes and adaptive optics, highlighting the importance of appropriate data and estimation methods for accurate measurements.
- Different methods (Dewan, HMNSP99, and Thorpe) were compared for estimating the refractive index structure constant (Cn2) in Huaihua, Hunan, revealing that the Thorpe method consistently outperformed the others.
- Findings indicated that HMNSP99's accuracy varied significantly with data resolution, while using ERA5 data showed that wind shear becomes a dominant factor in lower-resolution scenarios, with the temperature gradient's influence being minimal at high altitudes.
Article Abstract
The vertical profile of optical turbulence is a key factor in the performance design of astronomical telescopes and adaptive optics instruments. As site-testing campaigns are extremely expensive, the selection of appropriate spatial resolution data and estimation methods is extremely important. This study investigated the effect of using different methods (Dewan, HMNSP99, Thorpe method) to estimate the refractive index structure constant ( 2) using different resolution data (5 m, 25 m, ERA5 data) in Huaihua, Hunan. Compared with Dewan, HMNSP99 for estimating 2 using 5 m and 25 m resolution data, the Thorpe method almost always shows the best performance, with R above 0.75 and lower RMSE and MRE between estimated and measured 2. The results of 2 estimation using HMNSP99 at different resolution data varied widely, indicating that HMNSP99 is more sensitive to the data resolution and the temperature gradient is more sensitive to the resolution. Using ERA5 data, the two methods of estimating 2 using Dewan and HMNSP99 have close results. It indicates that the wind shear is the main factor when the spatial resolution of the data is reduced to a certain degree, and the contribution of temperature gradient is small in the high altitude turbulence.
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| http://dx.doi.org/10.1364/OE.493562 | DOI Listing |
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