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Most current astronomical adaptive optics (AO) systems rely on the availability of a bright star to measure the distortion of the incoming wavefront. Replacing the guide star with an artificial laser beacon alleviates this dependency on…

Astrophysics · Physics 2009-11-11 E. Steinbring , S. M. Faber , B. A. Macintosh , D. Gavel , E. L. Gates

A new instrument for spot profile analysis of electron diffraction - SPA-LEED - has been set up. The instrument works either with a transparent phosphor screen for visual inspection of the pattern or in its main mode with a channeltron for…

Materials Science · Physics 2015-01-30 U. Scheithauer , G. Meyer , M. Henzler

The new class of large telescopes, as the future ELT, are designed to work with Laser Guide Star (LGS) tuned to a resonance of atmosphere sodium atoms. This wavefront sensing technique presents complex issues for an application to big…

Instrumentation and Methods for Astrophysics · Physics 2018-04-20 M. Patti , M. Lombini , L. Schreiber , G. Bregoli , C. Arcidiacono , G. Cosentino , E. Diolaiti , I. Foppiani

This paper describes the data preprocessing and reduction methods together with SLODAR analysis and wind profiling techniques for GeMS: the Gemini MCAO System. The wavefront gradient measurements of the five GeMS's Shack-Hartmann sensors,…

Instrumentation and Methods for Astrophysics · Physics 2015-06-11 Angela Cortés , Benoit Neichel , Andrés Guesalaga , James Osborn , Francois Rigaut , Dani Guzman

The adaptive module of the 4.1-m SOAR telescope, SAM, corrects ground-layer turbulence using a UV laser guide star. It has been commissioned in 2013 and it is in regular science operation since 2014. SAM works with the CCD imager covering a…

Instrumentation and Methods for Astrophysics · Physics 2016-11-09 Andrei Tokovinin , Rolando Cantarutti , Roberto Tighe , Patricio Schurter , Manuel Martinez , Sandrine Thomas , Nicole van der Bliek

We present a systematic study of the internal mass structure of early-type galaxies (ETGs) based on 106 galaxy-scale strong gravitational lenses with background quasars, all having spectroscopic redshifts. From this parent sample, we select…

Astrophysics of Galaxies · Physics 2026-02-17 Ziyu Guo , Yun Chen , Yiping Shu , Jiaze Gao , Hui Li , Zizhao He , Jun Wang

We describe an experiment, located in south-east Colorado, USA, that measured aerosol optical depth profiles using two Lidar techniques. Two independent detectors measured scattered light from a vertical UV laser beam. One detector, located…

It is widely believed that adaptive optics only has a role in correcting turbulent wavefronts on large telescopes using very bright reference stars. Unfortunately these are very scarce and many astronomical targets require wavefront…

Instrumentation and Methods for Astrophysics · Physics 2019-11-19 Craig Mackay

Modern LiDAR sensors find increasing use in safety-critical applications. Therefore, highly accurate modeling of the system's behavior under demanding environmental conditions is necessary. In this paper, we present a modular structure to…

Instrumentation and Detectors · Physics 2022-08-09 Maximilian Fink , Michael Schardt , Valentin Baier , Kun Wang , Martin Jakobi , Alexander W. Koch

We present a tunable, continuous-wave (CW) laser system emitting at 213 nm, based on the frequency quadrupling of a single Ti:sapph laser. The setup features two sequential, cavity-enhanced second-harmonic generation (SHG) stages. The first…

Optics · Physics 2025-06-11 Lukas Möller , Stephan Hannig , Stefan Truppe , Simon Stellmer

The silicon nitride integration platform has been successful at realizing extremely low waveguide losses across the visible to infrared and components including high performance lasers, filters, resonators, stabilization cavities, and…

Using a laser-based ranging method for precise environmental 3D sensing, LiDAR has numerous applications in science and industry. However, conventional LiDAR face challenges in simultaneously achieving high ranging precision and fast…

Optics · Physics 2024-12-10 Lizong Dong , Qinggai Mi , Siyu Zhou , Yuetang Yang , Yuanzu Wang , Guanhao Wu

This work demonstrates a broadband tunable narrow-linewidth laser based on scattering-enhanced fiber, covering the E-S-C-L wavelength bands from 1337.47 nm to 1631.39 nm, with a total tuning span of 293.92 nm. The laser employs two…

Aims. We study the 2D spectral line profile of HARPS (High Accuracy Radial Velocity Planet Searcher), measuring its variation with position across the detector and with changing line intensity. The characterization of the line profile and…

Cn2 profile monitoring usually makes use of wavefront slope correlations or of scintillation pattern correlations. Wavefront slope correlations provide sensitivity to layers close to the receiving plane. In addition, scintillation…

Instrumentation and Methods for Astrophysics · Physics 2015-03-17 Clélia Robert , Juliette Voyez , Nicolas Védrenne , Laurent Mugnier

In a context of 3D mapping, it is very important to get accurate measurements from sensors. In particular, Light Detection And Ranging (LIDAR) measurements are typically treated as a zero-mean Gaussian distribution. We show that this…

Robotics · Computer Science 2019-08-29 Johann Laconte , Simon-Pierre Deschênes , Mathieu Labussière , François Pomerleau

In this paper, the interaction of a 1064 nm continuum-wave laser with inductively-coupled plasma generated in a fluorescent light bulb has been studied both experimentally and theoretically. The absorption coefficients pertaining to the…

Plasma Physics · Physics 2020-02-17 M. Fatih Yilmaz , M. Elif Tanriseven , Edgar Obonyo , Y. Danisman

Forthcoming astronomical imaging surveys will use weak gravitational lensing shear as a primary probe to study dark energy, with accuracy requirements at the 0.1% level. We present an implementation of the Metadetection shear measurement…

Instrumentation and Methods for Astrophysics · Physics 2023-05-16 Erin S. Sheldon , Matthew R. Becker , Michael Jarvis , Robert Armstrong , The LSST Dark Energy Science Collaboration

Stellar activity and planetary effects induce radial velocity (RV) offsets and cause temporal distortions in the shape of the stellar line profile. Hence, accurately probing the stellar line profile offers a wealth of information on both…

Earth and Planetary Astrophysics · Physics 2024-03-12 L. S. Dolan , E. J. W de Mooij , C. A. Watson , D. G. Jackson

A phase retrieval technique using a spatial light modulator (SLM) and a phase diffuser for a fast reconstruction of smooth wave fronts is demonstrated experimentally. Diffuse illumination of a smooth test object with the aid of a phase…

Optics · Physics 2015-06-11 Mostafa Agour , Percival F. Almoro , Claas Falldorf