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This article is the second of a series of articles aiming at proving the feasibility of the forecast of all the most relevant classical atmospherical parameters for astronomical applications (wind speed and direction, temperature, relative…

Instrumentation and Methods for Astrophysics · Physics 2013-09-27 Franck Lascaux , Elena Masciadri , Luca Fini

The weak-lensing science of the LSST project drives the need to carefully model and separate the instrumental artifacts from the intrinsic lensing signal. The dominant source of the systematics for all ground based telescopes is the spatial…

Instrumentation and Methods for Astrophysics · Physics 2015-05-20 M. James Jee , J. Anthony Tyson

We introduce and test an expression for calculating the variance of a physical field in three dimensions using only information contained in the two-dimensional projection of the field. The method is general but assumes statistical…

Astrophysics of Galaxies · Physics 2015-05-14 C. M. Brunt , C. Federrath , D. J. Price

Deep neural network models have shown a great potential in accelerating the simulation of fluid dynamic systems. Once trained, these models can make inference within seconds, thus can be extremely efficient. However, they suffer from a…

Fluid Dynamics · Physics 2022-02-23 Wenhui Peng , Zelong Yuan , Jianchun Wang

Adaptive Optics at mid-IR wavelengths has long been seen as either not necessary or easy. The impact of atmospheric turbulence on the performance of 8-10 meter class telescopes in the mid-IR is relatively small compared to other performance…

Instrumentation and Methods for Astrophysics · Physics 2015-05-14 R. Stuik , L. Jolissaint , S. Kendrew , S. Hippler , B. Brandl , L. Venema

Mesoscale model such as Meso-Nh have proven to be highly reliable in reproducing 3D maps of optical turbulence (see Refs. 1, 2, 3, 4) above mid-latitude astronomical sites. These last years ground-based astronomy has been looking towards…

Instrumentation and Methods for Astrophysics · Physics 2010-01-08 Franck Lascaux , Elena Masciadri , Susanna Hagelin , Jeffrey A. Stoesz

An analytical expression is given for the minimum of the time-delay induced wavefront error (also known as the servo-lag error) in Adaptive Optics systems under temporal prediction filtering. The analysis is based on the von K\'arm\'an…

Instrumentation and Methods for Astrophysics · Physics 2020-06-22 Niek Doelman

This paper presents a non-classic approach to narrow field astrometry that offers a significant improvement over conventional techniques due to enhanced reduction of atmospheric image motion. The method is based on two key elements:…

Astrophysics · Physics 2009-11-13 Petro F. Lazorenko , Galina A. Lazorenko

One important frontier for astronomical adaptive optics (AO) involves methods such as Multi-Object AO and Multi-Conjugate AO that have the potential to give a significantly larger field of view than conventional AO techniques. A second key…

Instrumentation and Methods for Astrophysics · Physics 2015-05-13 S. Mark Ammons , Luke Johnson , Edward A. Laag , Renate Kupke , Donald T. Gavel , Brian J. Bauman , Claire E. Max

Canary is the Multi-Object Adaptive Optics (MOAO) pathfinder for the future MOAO-assisted Integral-Field Units (IFU) proposed for Extremely Large Telescopes (ELT). The MOAO concept relies on tomographically reconstructing the turbulence…

Instrumentation and Methods for Astrophysics · Physics 2016-11-23 O. A. Martin , C. M. Correia , E. Gendron , G. Rousset , F. Vidal , T. J. Morris , A. G. Basden , R. M. Myers , Y. H. Ono , B. Neichel , T. Fusco

We recently developed a new approach to get a stabilized image from a sequence of frames acquired through atmospheric turbulence. The goal of this algorihtm is to remove the geometric distortions due by the atmosphere movements. This method…

Computer Vision and Pattern Recognition · Computer Science 2024-11-06 Yu Mao , Jerome Gilles

Turbulence is a key element of the dynamics of astrophysical fluids, including those of interstellar medium, clusters of galaxies and circumstellar regions. Turbulent motions induce Doppler shifts of observable emission and absorption lines…

Astrophysics · Physics 2009-03-27 A. Chepurnov , A. Lazarian

Astronomers working with faint targets will benefit greatly from improved image quality on current and planned ground-based telescopes. At present, most adaptive optic systems are targeted at the highest resolution with bright guide stars.…

Instrumentation and Methods for Astrophysics · Physics 2020-01-30 Craig Mackay

Online system identification algorithms are widely used for monitoring, diagnostics and control by continuously adapting to time-varying dynamics. Typically, these algorithms consider a model structure that lacks parsimony and offers…

Systems and Control · Electrical Eng. & Systems 2025-04-28 Koen Classens , Rodrigo A. González , Tom Oomen

Optical beams and starlight distorted by atmospheric turbulence can be corrected with adaptive optics systems to enable efficient coupling into single-mode fibers. Deformable mirrors, used to flatten the wavefront in astronomical…

Adaptive optics (AO) systems and image reconstruction algorithms are indispensable tools when it comes to high-precision astrometry. In this paper, we analyze the potential of combining both techniques, i.e. by applying image reconstruction…

Instrumentation and Methods for Astrophysics · Physics 2019-03-13 Felix Bosco , Jörg-Uwe Pott , Rainer Schödel

Atmospheric turbulence, a common phenomenon in daily life, is primarily caused by the uneven heating of the Earth's surface. This phenomenon results in distorted and blurred acquired images or videos and can significantly impact downstream…

Computer Vision and Pattern Recognition · Computer Science 2024-02-13 Xijun Wang , Santiago López-Tapia , Aggelos K. Katsaggelos

Strong turbulence conditions create amplitude aberrations through the effects of near-field diffraction. When integrated over long optical path lengths, amplitude aberrations (seen as scintillation) can nullify local areas in the recorded…

Instrumentation and Methods for Astrophysics · Physics 2020-12-30 Justin R. Crepp , Stanimir O. Letchev , Sam J. Potier , Joshua H. Follansbee , Nicholas T. Tusay

With Rytov approximation theory, we derive the analytic expression of detection probability of Airy vortex beam carrying orbital angular momentum (OAM) through an anisotropic weak oceanic turbulence. We investigate the influences of…

Classical Physics · Physics 2018-10-17 Xinguang Wang , Zhen Yang , Shengmei Zhao

Atmospheric turbulence distorts visual imagery and is always problematic for information interpretation by both human and machine. Most well-developed approaches to remove atmospheric turbulence distortion are model-based. However, these…

Computer Vision and Pattern Recognition · Computer Science 2022-05-10 Nantheera Anantrasirichai
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