Measurement of dome turbulence intensity from scintillation pattern in the pupil of the telescope
Victor G. Kornilov, Matwey V. Kornilov, Boris S. Safonov, Anton S. Mironov, Dmitry V. Cheryasov, Igor A. Gorbunov, Ivan A. Strakhov
Published: 2025/9/2
Abstract
We present measurements of optical turbulence (OT) power inside the telescope dome using an instrument registering fluctuations of intensity of a bright star at a plane conjugated to -2 km below the pupil of the telescope - Domecam. The measurements were conducted at the 2.5-m telescope of Caucasian Mountain Observatory of Sternberg Astronomical Institute Lomonosov Moscow State University in period 2022-2024 in different ambient conditions. The instrument was validated against Multi Aperture Scintillation Sensor. Using simultaneous observations with a speckle imager mounted at 2.5-m telescope, we demonstrate that dome OT power measured with Domecam can be converted into delivered image quality (DIQ) assuming von Karman model with outer scale of 0.57 +/- 0.1 m for dome turbulence. Dome turbulence increases median of expected distribution of DIQ for the 2.5-m telescope from 0.90'' to 1.12''.