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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

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

Adaptive optics (AO) is a technology in modern ground-based optical telescopes to compensate the wavefront distortions caused by atmospheric turbulence. One method that allows to retrieve information about the atmosphere from telescope data…

Instrumentation and Methods for Astrophysics · Physics 2018-04-04 Tapio Helin , Stefan Kindermann , Jonatan Lehtonen , Ronny Ramlau

These last years ground-based astronomy has been looking towards Antarctica, especially its summits and the internal continental plateau where the optical turbulence (OT) appears to be confined in a shallow layer close to the surface.…

Instrumentation and Methods for Astrophysics · Physics 2010-01-04 F. Lascaux , E. Masciadri , S. Hagelin , J. Stoesz

We for the first time report the truncated diffraction with a triangular aperture of the SU(2) geometric modes and propose a method to detect the complicated orbital angular momentum (OAM) of an SU(2) wave-packet, to the best of our…

Optics · Physics 2018-10-17 Yijie Shen , Xing Fu , Mali Gong

Knowledge about the characteristics of the atmospheric boundary layer is vital for the understanding of redistribution of air and suspended contents that are particularly driven by turbulent motions. Despite many modelling studies, detailed…

Atmospheric and Oceanic Physics · Physics 2022-09-14 Hans van Haren , Fred. C. Bosveld

We present a simple method of extracting a small number of reference optical turbulence and wind profiles from a large dataset for single conjugate and extreme adaptive optics simulations. These reference profiles can be used in slow…

Instrumentation and Methods for Astrophysics · Physics 2022-10-18 O. J. D. Farley

A Single Star Scidar system(SSS) has been developed for remotely sensing atmospheric turbulence profiles. The SSS consists of computing the spatial auto/cross-correlation functions of short exposure images of the scintillation patterns…

Instrumentation and Methods for Astrophysics · Physics 2013-03-20 Li-Yong Liu , Yong-Qiang Yao , Jean Vernin , Hong-Shuai Wang , Jia Yin , Xuan Qian

The effect of stellar scintillation on the accuracy of photometric measurements is analyzed. We obtain a convenient form of estimaton of this effect in the long exposure regime, when the turbulence shift produced by the wind is much larger…

Instrumentation and Methods for Astrophysics · Physics 2011-02-01 V. Kornilov

We report site testing results obtained in night-time during the polar autumn and winter at Dome C. These results were collected during the first Concordia winterover by A. Agabi. They are based upon seeing and isoplanatic angle monitoring,…

The sodium laser guide star (sLGS) adaptive optics (AO) system has become an essential component for large ground-based optical/infrared telescope. The performance of the AO system can be significantly hindered if the on-sky spot profile of…

Instrumentation and Methods for Astrophysics · Physics 2021-11-24 Jian Huang , Lu Feng , Kai Jin , Min Li , Gongchang Wang

The Very Local Interstellar Medium (VLISM) contains clouds which consist of partially-ionized plasma. These clouds can be effectively diagnosed via high resolution optical and ultraviolet spectroscopy of the absorption lines they form in…

Astrophysics of Galaxies · Physics 2015-05-19 Steven R. Spangler , Allison H. Savage , Seth Redfield

Optical angular momentum (OAM) in light beams is manifested as the two-dimensional spatial distribution of its complex amplitude, necessitating a 2D detector for its measurement. Here we present a novel speckle-based machine learning…

Optics · Physics 2024-12-19 Vijay Kumar , Purnesh Singh Badavath

Developed at the Observatoire de la C\^ote d'Azur (OCA) within the framework of the PICARD space mission (Thuillier et al., 2006) and with support from the french spatial agency (CNES), MISOLFA (Moniteur d'Images Solaires Franco-Alg\'erien)…

Instrumentation and Methods for Astrophysics · Physics 2014-12-16 T. Corbard , A. Irbah , P. Assus , C. Dufour , M. Fodil , F. Morand , C. Renaud , E. Simon

The low infrared background and high atmospheric transparency are the principal advantages of Antarctic Plateau sites for astronomy. However, the poor seeing (between one and three arcseconds) negates much of the sensitivity improvements…

Astrophysics · Physics 2009-11-07 James P. Lloyd , Ben R. Oppenheimer , James R. Graham

The free-space optical channel has the potential to facilitate inexpensive, wireless communication with fiber-like bandwidth under short deployment timelines. However, atmospheric effects can significantly degrade the reliability of a…

Information Theory · Computer Science 2008-04-02 Nick Letzepis , Albert Guillen i Fabregas

Ground-based direct imaging surveys like the Gemini Planet Imager Exoplanet Survey (GPIES) rely on Adaptive Optics (AO) systems to image and characterize exoplanets that are up to a million times fainter than their host stars. One factor…

Orbital angular momentum (OAM), a topological degree of freedom of light, is theoretically invariant under continuous deformations; yet, its physical observability degrades precipitously in complex media, creating a fundamental…

Optics · Physics 2026-03-06 Shuailing Wang , Jingping Xu , Yaping Yang

We present the overview of the MOSE project (MOdeling ESO Sites) aiming at proving the feasibility of the forecast of the classical atmospherical parameters (wind speed intensity and direction, temperature, relative humidity) and the…

Instrumentation and Methods for Astrophysics · Physics 2013-09-27 E. Masciadri , F. Lascaux , L. Fini

Our knowledge of the circumgalactic medium (CGM) is mostly based on quasar absorption-line measurements. These have uncovered a multiphase medium that is likely highly turbulent, but constraints of this turbulence are limited to…

Astrophysics of Galaxies · Physics 2023-08-24 Brad Koplitz , Edward Buie , Evan Scannapieco
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