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

Beltramo-Martin, Olivier; Bharmal, Nazim Ali; Correia, Carlos

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 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 C2n(h) and L0(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 C2n(h) and L0(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.

Citation

Beltramo-Martin, O., Bharmal, N. A., & Correia, C. (2019). PEPITO: atmospheric Profiling from short-Exposure focal Plane Images in seeing-limiTed mOde. Monthly Notices of the Royal Astronomical Society, 486(2), 2032-2041. https://doi.org/10.1093/mnras/stz979

• Journal Article Type: Article
• Acceptance Date: Apr 4, 2019
• Online Publication Date: Apr 10, 2019
• Publication Date: Jun 30, 2019
• Deposit Date: Apr 4, 2019
• Publicly Available Date: Apr 16, 2019
• Journal: Monthly Notices of the Royal Astronomical Society
• Print ISSN: 0035-8711
• Electronic ISSN: 1365-2966
• Publisher: Royal Astronomical Society
• Peer Reviewed: Peer Reviewed
• Volume: 486
• Issue: 2
• Pages: 2032-2041
• DOI: https://doi.org/10.1093/mnras/stz979
• Public URL: https://durham-repository.worktribe.com/output/1299313
• Related Public URLs: https://arxiv.org/abs/1901.10701