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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

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

In unmanned aerial vehicle (UAV)-assisted orthogonal frequency division multiplexing (OFDM) systems, the potential advantage of the line-of-sight (LoS) path, characterized by its high probability of existence, has not been fully harnessed,…

Other Computer Science · Computer Science 2024-04-04 Chaojin Qing , Zhiying Liu , Wenquan Hu , Yinjie Zhang , Xi Cai , Pengfei Du

The axis tilt of light beam in optical system would introduce the dispersion of orbital angular momentum (OAM) spectrum. To deal with it, a two-step method is proposed and demonstrated. First, the tilt angle of optical axis is identified…

Optics · Physics 2020-04-27 Peng Zhao , Shikang Li , Yu Wang , Xue Feng , Kaiyu Cui , Fang Liu , Wei Zhang , Yidong Huang

The multi-object spectrograph (MOS) has been the benchmark for the current generation of astronomical spectrographs, valued for its ability to acquire the spectra of hundreds of objects simultaneously. In the last two decades, the digital…

Instrumentation and Methods for Astrophysics · Physics 2022-10-03 Shaojie Chen , Matthew C. H. Leung , Xuefeng Yao , Suresh Sivanandam , Isabelle Sanders , Rosalind Liang

Atmospheric turbulence and precise measurement of the astrometric baseline vector between any two telescopes are two major challenges in implementing phase referenced interferometric astrometry and imaging. They limit the performance of a…

Instrumentation and Methods for Astrophysics · Physics 2018-03-14 N. Anugu , A. Amorim , P. Gordo , F. Eisenhauer , O. Pfuhl , M. Haug , E. Wiezorrek , J. Lima , G. Perrin , W. Brandner , C. Straubmeier , J. -B. Le Bouquin , P. J. V Garcia

Modern ground-based telescopes rely on a technology called adaptive optics (AO) in order to compensate for the loss of image quality caused by atmospheric turbulence. Next-generation AO systems designed for a wide field of view require a…

Numerical Analysis · Mathematics 2015-11-24 Tapio Helin , Stefan Kindermann , Daniela Saxenhuber

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

The Simons Observatory is a ground-based cosmic microwave background survey experiment that consists of three 0.5 m small-aperture telescopes and one 6 m large-aperture telescope, sited at an elevation of 5200 m in the Atacama Desert in…

Characterisation of atmospheric optical turbulence is crucial for the design and operation of modern ground-based optical telescopes. In particular, the effective application of adaptive optics correction on large and extremely large…

Instrumentation and Methods for Astrophysics · Physics 2023-03-02 Saavidra Perera , Richard W. Wilson , Tim Butterley , James Osborn , Ollie J. D. Farley , Douglas J. Laidlaw

There are different techniques to sense the wavefront phase-distortions due to atmospheric turbulence. Curvature sensors are practical in their sensitivity being adjustable to the prevailing atmospheric conditions. Even at the best sites,…

Instrumentation and Methods for Astrophysics · Physics 2015-05-19 Aglae Kellerer , Mark Chun , Christ Ftaclas

We present an experiment set to address a standard specification aiming at avoiding local turbulence inside the Coud\'e train of telescopes. Namely, every optical surface should be kept within a 1.5$^\circ$ range around ambient temperature.…

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

The Burst Observer and Optical Transient Exploring System (BOOTES) is a network of telescopes that allows the continuous monitoring of transient astrophysical sources. It was originally devoted to the study of the optical emission from…

Instrumentation and Methods for Astrophysics · Physics 2014-08-20 M. D. Caballero-Garcia , M. Jelinek , A. Castro-Tirado , R. Hudec , R. Cunniffe , O. Rabaza , L. Sabau-Graziati

The Generalised Differential Image Motion Monitor (GDIMM) was proposed a few years ago as a new generation instrument for turbulence monitoring. It measures integrated parameters of the optical turbulence, i.e the seeing, isoplanatic angle,…

Instrumentation and Methods for Astrophysics · Physics 2020-12-18 Eric Aristidi , Yan Fantéï-Caujolle , Aziz Ziad , Julien Chabé , Christophe Giordano , Catherine Renaud , Alohotsy Rafalimanana

The Indian Institute of Astrophysics (IIA) is developing a Multi-Conjugate Adaptive Optics (MCAO) system for the Kodaikanal Tower Telescope (KTT). In this context, we have measured the daytime turbulence strength profile at the Kodaikanal…

Instrumentation and Methods for Astrophysics · Physics 2024-07-22 Saraswathi Kalyani Subramanian , Sridharan Rengaswamy , Prasanna Gajanan Deshmukh , Binukumar G. Nair , Mahesh Babu S

Monitoring the evolution of the anthropogenic light emissions is a priority task in light pollution research. Among the complementary approaches that can be adopted to achieve this goal stand out those based on measuring the direct radiance…

Instrumentation and Methods for Astrophysics · Physics 2024-10-31 Salvador Bará

We experimentally measure the monochromatic transmission matrix (TM) of an optical multiple scattering medium using a spatial light modulator together with a phase-shifting interferometry measurement method. The TM contains all information…

Optics · Physics 2015-05-28 S. M. Popoff , G. Lerosey , M. Fink , A. C. Boccara , S. Gigan

Forecast of optical turbulence and atmospheric parameters relevant for ground-based astronomy is becoming an important goal for telescope planning and AO instruments optimization in several major telescope. Such detailed and accurate…

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

An adaptive optics system with a single deformable mirror is being implemented on the THEMIS 90cm solar telescope. This system is designed to operate in the visible and is required to be as robust as possible in order to deliver the best…

Instrumentation and Methods for Astrophysics · Physics 2021-01-11 Michel Tallon , Éric Thiébaut , Maud Langlois , Bernard Gelly , Richard Douet , Clémentine Béchet , Loïc Denis , Gil Moretto
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