First on-sky demonstration of a scintillation correction technique using tomographic wavefront sensing

ABSTRACT Scintillation noise significantly limits high precision ground-based photometry of bright stars. In this paper, we present the first ever on-sky demonstration scintillation correction. The technique uses tomographic wavefront sensing to estimate spatial-temporal intensity fluctuations induced by altitude optical turbulence. With an altitudes and relative strengths turbulent layers above telescope, sensor data from multiple guide stars can be combined phase aberrations at each through use a algorithm. This 3D model then used across telescope pupil via Fresnel propagation. measured photometric for given target within field view corrected effects using in post-processing. A simple proof-of-concept experiment stereo-SCIDAR turbulence profiler attached 2.5 m Isaac Newton Telescope was performed range exposure times Orion Trapezium cluster as reference results well simulations estimating expected performance full AO system with laser are presented. On-sky, index reduced on average factor 1.9, peak 3.4. For system, expect achieve maximum reduction ∼25.