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Related papers: Near ground horizontal high resolution $C_n^2$ pro…

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In addition to astro-meteorological parameters, such as seeing, coherence time and isoplanatic angle, the vertical profile of the Earth's atmospheric turbulence strength and velocity is important for instrument design, performance…

Instrumentation and Methods for Astrophysics · Physics 2018-09-24 James Osborn , Marc Sarazin

A six-night optical turbulence monitoring campaign has been carried at Cerro Paranal observatory in February and March, 2023 to facilitate the development and characterisation of two novel atmospheric site monitoring instruments - the…

Instrumentation and Methods for Astrophysics · Physics 2024-02-15 Ryan Griffiths , Lisa Bardou , Timothy Butterley , James Osborn , Richard Wilson , Edison Bustos , Andrei Tokovinin , Miska Le Louarn , Angel Otarola

We present an optical metrology system for characterization of topography of micro/nano-structures on a surface or embedded in a semi-transparent material. Based on the principles of scatterometry, where the intensity of scattered light is…

Instrumentation and Detectors · Physics 2016-01-15 Morten Hannibal Madsen , Poul-Erik Hansen

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

Analyzing high-dimensional data with manifold learning algorithms often requires searching for the nearest neighbors of all observations. This presents a computational bottleneck in statistical manifold learning when observations of…

Machine Learning · Computer Science 2022-03-11 Fan Cheng , Anastasios Panagiotelis , Rob J Hyndman

The mesoscale model Meso-NH is used to simulate the optical turbulence at Mt Graham (Arizona, USA), site of the Large Binocular Telescope. Measurements of the CN2-profiles obtained with a generalized scidar from 41 nights are used to…

Instrumentation and Methods for Astrophysics · Physics 2011-05-16 S. Hagelin , E. Masciadri , F. Lascaux

Improving the accuracy of soil moisture estimation is required for advancing irrigation scheduling and water conservation efforts. Central to this task are soil hydraulic parameters, which govern moisture dynamics but are rarely known…

Systems and Control · Electrical Eng. & Systems 2025-06-06 Bernard T. Agyeman , Erfan Orouskhani , Mohamed Naouri , Willemijn Appels , Maik Wolleben , Jinfeng Liu , Sirish L. Shah

We developed a mid-infrared optical frequency comb-based Fourier-transform spectrometer and performed a line-shape study of the fundamental vibrational band of CO perturbed by N${_2}$, which is crucial for atmospheric science and…

The Profiler of Moon Limb is a recent instrument dedicated to the monitoring of optical turbulence profile of the atmosphere. Fluctuations of the Moon or the Sun limb allow to evaluate the index refraction structure constant C_n^2(h) and…

Instrumentation and Methods for Astrophysics · Physics 2020-02-13 Eric Aristidi , Aziz Ziad , Yan Fantéï-Caujolle , Julien Chabé , Christophe Giordano , Catherine Renaud , Henri Lantéri

A method is described to model the magnetic field in the vicinity of constellations of multiple satellites using field and plasma current measurements. This quadratic model has the properties that the divergence is zero everywhere and…

In this paper I describe a simple numerical procedure to compute synthetic horizon altitude profiles for any given site. The method makes use of a simplified model of local Earth's curvature, and it is based on the availability of digital…

History and Philosophy of Physics · Physics 2015-05-28 Ferdinando Patat

We use the ultra-violet (UV) spectra in the range 230--300 nm from the SCanning Imaging Absorption spectroMeter for Atmospheric CHartographY (SCIAMACHY) to retrieve the nitric oxide (NO) number densities from atmospheric emissions in the…

Atmospheric and Oceanic Physics · Physics 2018-08-08 Stefan Bender , Miriam Sinnhuber , John P. Burrows , Martin Langowski , Bernd Funke , Manuel López-Puertas

Images of near-field SAR contains spatial-variant sidelobes and clutter, subduing the image quality. Current image restoration methods are only suitable for small observation angle, due to their assumption of 2D spatial-invariant…

Signal Processing · Electrical Eng. & Systems 2022-10-06 Wensi Zhang , Xiaoling Zhang , Xu Zhan , Yuetonghui Xu , Jun Shi , Shunjun Wei

To study nanostructures on substrates, surface-sensitive reflection-geometry scattering techniques such as grazing incident small angle x-ray scattering are commonly used to yield an averaged statistical structural information of the…

Reconstructing the 3D shape of an object using several images under different light sources is a very challenging task, especially when realistic assumptions such as light propagation and attenuation, perspective viewing geometry and…

Computer Vision and Pattern Recognition · Computer Science 2020-09-15 Fotios Logothetis , Ignas Budvytis , Roberto Mecca , Roberto Cipolla

Precise sensor calibration is critical for autonomous vehicles as a prerequisite for perception algorithms to function properly. Rotation error of one degree can translate to position error of meters in target object detection at large…

Robotics · Computer Science 2025-06-24 Zhongyuan Li , Honggang Gou , Ping Li , Jiaotong Guo , Mao Ye

We report on precision spectroscopy of sub-wavelength confined molecular gases. This was obtained by rovibrational selective reflection of $\mathrm{NH_3}$ and $\mathrm{SF_6}$ gases using a quantum cascade laser at $\lambda\approx 10.6 \mu…

Mid-infrared (mid-IR) spectroscopy is a crucial workhorse for a plethora of analytical applications and is suitable for diverse materials, including gases, polymers or biological tissue. However, this technologically significant wavelength…

Optics · Physics 2022-02-23 Paul Kaufmann , Helen M. Chrzanowski , Aron Vanselow , Sven Ramelow

Coherent wide parameter-space searches for continuous gravitational waves are typically limited in sensitivity by their prohibitive computing cost. Therefore semi-coherent methods (such as StackSlide) can often achieve a better sensitivity.…

General Relativity and Quantum Cosmology · Physics 2015-06-03 Reinhard Prix , Miroslav Shaltev

Robust local feature representations are essential for spatial intelligence tasks such as robot navigation and augmented reality. Establishing reliable correspondences requires descriptors that provide both high discriminative power and…

Computer Vision and Pattern Recognition · Computer Science 2026-01-15 Haodi Yao , Fenghua He , Ning Hao , Yao Su