PEPITO: atmospheric Profiling from short-Exposure focalPlane Images in seeing-limiTed mOde

Abstract

Atmospheric profiling is a requirement for controlling wide-field Adaptive Optics (AO) instruments, analyzing the AO performance with respect to the observing conditions and predicting the Point Spread Function (PSF) spatial variations. We present PEPITO, a new concept for profiling atmospheric turbulence from {\em post~facto} tip-tilt (TT) corrected short-exposure images. PEPITO utilizes the anisokinetism effect in the images between several stars separated from a reference star, and then produces the profile estimation using a model-fitting methodology, by fitting to the long exposure TT-corrected PSF. PEPITO has a high sensitivity to both $C_n^2(h)$ and $L_0(h)$ by relying on the full telescope aperture and a large field of view. It then obtains a high vertical resolution (1\,m-400\,m) configurable by the camera pixel scale, taking advantage of fast statistical convergence (of order of tens of seconds). With only a short exposure-capable large format detector and a numerical complexity independent of the telescope diameter, PEPITO perfectly suits accurate profiling for night optical turbulence site characterization or adaptive optics instruments operations. We demonstrate, in simulation, that the $C_n^2(h)$ and $L_0(h)$ can be estimated to better than 1\% accuracy, from fitted PSFs of magnitude V=11 on a D=0.5\,m telescope with a 10 arcmin field of view.

arXiv comment11 pages, 14 figures, accepted 2019 April 04, submitted 2019 January 29

References in corpus (18)

• Optical turbulence profiling with Stereo-SCIDAR for VLT and ELT
• Optical turbulence forecast: ready for an operational application
• Atmospheric turbulence forecasting with a General Circulation Model for Cerro Paranal
• Origin of the asymmetry of the wind driven halo observed in high contrast images
• Modelling astronomical adaptive optics performance with temporally-filtered Wiener reconstruction of slope data
• On-Line Long-Exposure Phase Diversity: a Powerful Tool for Sensing Quasi-Static Aberrations of Extreme Adaptive Optics Imaging Systems
• Spatio-angular Minimum-variance Tomographic Controller for Multi-Object Adaptive Optics systems
• Numerical estimation of wavefront error breakdown in adaptive optics
• On the comparison between MASS and G-SCIDAR techniques
• Statistics of Turbulence Parameters at Maunakea using multiple wave-front sensor data of RAVEN
• Multi time-step wave-front reconstruction for tomographic Adaptive-Optics systems
• Optimizing the accuracy and efficiency of optical turbulence profiling using adaptive optics telemetry for extremely large telescopes
• Wave-front error breakdown in LGS MOAO validated on-sky by CANARY
• Multi-star Turbulence Monitor: A new technique to measure optical turbulence profiles
• Representative optical turbulence profiles for ESO Paranal by hierarchical clustering
• Fast Iterative Tomographic Wave-front Estimation with Recursive Toeplitz Reconstructor Structure for Large Scale Systems
• Towards a reliability assessment of the Cn2 and wind speed vertical profiles retrieved from GeMS
• Focal plane $C_n^2(h)$ profiling based on single conjugate adaptive optics compensated images