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Related papers: Optical Turbulence Characterization at LAMOST Site…

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ALTA project has been active since 2016, providing, at LBT observatory site, forecasts of atmospheric parameters, such as temperature, wind speed and direction, relative humidity and precipitable water vapor, and optical turbulence…

Instrumentation and Methods for Astrophysics · Physics 2022-10-21 A. Turchi , E. Masciadri , C. Veillet

Turbulent fluctuations of the atmospheric refraction index, so-called optical turbulence, can significantly distort propagating laser beams. Therefore, modeling the strength of these fluctuations ($C_n^2$) is highly relevant for the…

Atmospheric and Oceanic Physics · Physics 2023-08-11 Maximilian Pierzyna , Rudolf Saathof , Sukanta Basu

Long-range imaging inevitably suffers from atmospheric turbulence with severe geometric distortions due to random refraction of light. The further the distance, the more severe the disturbance. Despite existing research has achieved great…

Computer Vision and Pattern Recognition · Computer Science 2024-07-18 Shengqi Xu , Run Sun , Yi Chang , Shuning Cao , Xueyao Xiao , Luxin Yan

Adaptive Optics (AO) systems have become integral for ground-based astronomy. Based on the scientific case, there are various flavours of AO systems. Measuring the turbulence strength profile ($C_N^2(h)$) and other site characteristics is…

Instrumentation and Methods for Astrophysics · Physics 2023-10-19 Saraswathi Kalyani Subramanian , Sridharan Rengaswamy

Advanced adaptive optics (AO) instruments on ground-based telescopes require accurate knowledge of the atmospheric turbulence strength as a function of altitude. This information assists point spread function reconstruction, AO temporal…

Ground-based solar observations are severely affected by Earth's turbulent atmosphere. As a consequence, observed image quality and prevailing seeing conditions are closely related. Partial correction of image degradation is nowadays…

Instrumentation and Methods for Astrophysics · Physics 2021-02-10 Robert Kamlah , Meetu Verma , Andrea Diercke , Carsten Denker

Point Spread Function (PSF) for imaging through inhomogeneous refractive medium, such as atmospheric turbulence is bounded by three constraints [Charnotskii, Opt. Eng., 52, 04600, (2013)]. PSF is non-negative, band-limited, and the third…

Optics · Physics 2022-07-06 Mikhail Charnotskii

The search for Earth-like exoplanets requires high-contrast and high-angular resolution instruments, which designs can be very complex: they need an adaptive optics system to compensate for the effect of the atmospheric turbulence on image…

Instrumentation and Methods for Astrophysics · Physics 2020-12-16 Lucie Leboulleux , Raphaël Galicher , Eric Gendron , Pierre Baudoz , Gérard Rousset

Turbulence influences the structure and dynamics of molecular clouds, and plays a key role in regulating star formation. We therefore need methods to accurately infer turbulence properties of molecular clouds from position-position-velocity…

Astrophysics of Galaxies · Physics 2025-09-12 Jayashree Narayan , Aris Tritsis , Christoph Federrath

We describe a procedure by which a long ($\gtrsim 1\,\mathrm{km}$) optical path through atmospheric turbulence can be experimentally simulated in a controlled fashion and scaled down to distances easily accessible in a laboratory setting.…

We use spatio-temporal cross-correlations of slopes from five Shack-Hartmann wavefront sensors to analyse the temporal evolution of the atmospheric turbulence layers at different altitudes. The focus is on the verification of the frozen…

Instrumentation and Methods for Astrophysics · Physics 2014-02-28 Andrés Guesalaga , Benoit Neichel , Angela Cortes , Clémentine Béchet , Dani Guzmán

Atmospheric turbulence deteriorates the quality of images captured by long-range imaging systems by introducing blur and geometric distortions to the captured scene. This leads to a drastic drop in performance when computer vision…

Computer Vision and Pattern Recognition · Computer Science 2022-04-20 Nithin Gopalakrishnan Nair , Kangfu Mei , Vishal M. Patel

We have experimentally studied the degradation of mode purity for light beams carrying orbital angular momentum (OAM) propagating through simulated atmospheric turbulence. The turbulence is modeled as a randomly varying phase aberration,…

During electro-optical testing of the camera for the upcoming Vera C. Rubin Observatory Legacy Survey of Space and Time, a unique low-signal pattern was found in differenced pairs of flat images used to create photon transfer curves, with…

Instrumentation and Methods for Astrophysics · Physics 2024-11-21 John Banovetz , Yousuke Utsumi , Joshua Meyers , Maya Beleznay , Andrew Rasmussen , Aaron Roodman

We investigate the ellipticity of the point-spread function (PSF) produced by imaging an unresolved source with a telescope, subject to the effects of atmospheric turbulence. It is important to quantify these effects in order to understand…

Astrophysics · Physics 2011-02-11 W. H. de Vries , S. S. Olivier , S. J. Asztalos , L. J. Rosenberg , K. L. Baker

Whole atmosphere seeing \beta_0 is the most important parameter in site testing measurements. Estimation of the seeing from a variance of differential image motion is always biased by a non-zero DIMM exposure, which results in a wind…

Instrumentation and Methods for Astrophysics · Physics 2015-05-30 V. Kornilov , B. Safonov

The image quality from Ground-Layer Adaptive Optics (GLAO) can be gradually increased with decreased contiguous field of view. This trade-off is dependent on the vertical profile of the optical turbulence (Cn2 profiles). It is known that…

Instrumentation and Methods for Astrophysics · Physics 2009-12-23 J. Stoesz , E. Masciadri , F. Lascaux , S. Hagelin

Ground-based astronomy is severely limited by the atmospheric turbulence, resulting in a large Point-Spread-Function (PSF) and poor imaging resolution. Even imaging with Adaptive Optics (AO) cannot completely correct the aberrated…

Instrumentation and Methods for Astrophysics · Physics 2019-01-18 R. JL. Fétick , B. Neichel , L. M. Mugnier , A. Montmerle-Bonnefois , T. Fusco

Scintillation noise due to the Earth's turbulent atmosphere can be a dominant noise source in high-precision astronomical photometry when observing bright targets from the ground. Here we describe the phenomenon of scintillation from its…

Instrumentation and Methods for Astrophysics · Physics 2015-08-06 J. Osborn , D. Föhring , V. S. Dhillon , R. W. Wilson

The influence of atmospheric turbulence on acquired surveillance imagery poses significant challenges in image interpretation and scene analysis. Conventional approaches for target classification and tracking are less effective under such…

Computer Vision and Pattern Recognition · Computer Science 2023-05-31 Disen Hu , Nantheera Anantrasirichai
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