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Related papers: Cn2 and wind profiler method to quantify the froze…

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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

Nullifying the servo bandwidth errors improves the strehl ratio by a substantial quantity in adaptive optics systems. An effective method for predicting atmospheric turbulence to reduce servo bandwidth errors in real time closed loop…

Instrumentation and Methods for Astrophysics · Physics 2011-09-14 Akondi Vyas , M B Roopashree , B Raghavendra Prasad

The precise reconstruction of the turbulent volume is a key point in the development of new-generation Adaptive Optics systems. We propose a new Cn2 profilometry method named CO-SLIDAR (COupled Slope and scIntillation Detection And…

Instrumentation and Methods for Astrophysics · Physics 2015-06-05 Juliette Voyez , Clélia Robert , Vincent Michau , Jean Marc Conan , Thierry Fusco

This study introduces OTCliM (Optical Turbulence Climatology using Machine learning), a novel approach for deriving comprehensive climatologies of atmospheric optical turbulence strength ($C_n^2$) using gradient boosting machines. OTCliM…

Atmospheric and Oceanic Physics · Physics 2025-06-02 Maximilian Pierzyna , Sukanta Basu , Rudolf Saathof

As telescopes become larger, into the era of ~40 m Extremely Large Telescopes, the high- resolution vertical profile of the optical turbulence strength is critical for the validation, optimization and operation of optical systems. The…

Instrumentation and Methods for Astrophysics · Physics 2017-01-11 J. Osborn , T. Butterley , M. J. Townson , A. P. Reeves , T. J. Morris , R. W. Wilson

In two recent papers the mesoscale model Meso-NH, joint with the Astro-Meso-NH package, has been validated at Dome C, Antarctica, for the characterization of the optical turbulence. It has been shown that the meteorological parameters…

Instrumentation and Methods for Astrophysics · Physics 2010-11-09 Franck Lascaux , Elena Masciadri , Susanna Hagelin

Dual-tip phase-detection probes can be used to measure flow properties in gas-liquid flows. Traditionally, time-averaged interfacial velocities have been obtained through cross-correlation analysis of long time-series of phase fraction…

Fluid Dynamics · Physics 2020-01-14 Matthias Kramer , Benjamin Hohermuth , Daniel Valero , Stefan Felder

It's difficult to accurately predict the flow with shock waves over an aircraft due to the flow's strongly nonlinear characteristics. In this study, we propose an accuracy-enhanced flow prediction method that fuses deep learning and…

Fluid Dynamics · Physics 2024-05-27 Xuyi Jia , Chunlin Gong , Wen Ji , Chunna Li

Weather regimes provide a useful framework for describing large-scale atmospheric variability and its impacts on regional weather. Despite extensive study, there is still no universally accepted definition or method for identifying weather…

Algebraic Topology · Mathematics 2026-05-21 Soheil Anbouhi

Prior statistical knowledge of the atmospheric turbulence is essential for designing, optimizing and evaluating tomographic adaptive optics systems. We present the statistics of the vertical profiles of $C_N^2$ and the outer scale at…

Instrumentation and Methods for Astrophysics · Physics 2017-01-11 Yoshito H. Ono , Carlos M. Correia , Dave R. Andersen , Olivier Lardiere , Shin Oya , Masayuki Akiyama , Kate Jackson , Colin Bradley

Atmospheric profiling is a requirement for controlling wide-field Adaptive Optics (AO) instruments, analyzing the AO performance with respect to the observing conditions and predicting the Point Spread Function (PSF) spatial variations. We…

Instrumentation and Methods for Astrophysics · Physics 2019-04-17 Olivier Beltramo-Martin , Nazim A. Bharmal , Carlos M. Correia

The estimation of atmospheric turbulence parameters is of relevance for: a) site evaluation & characterisation; b) prediction of the point spread function; c) live assessment of error budgets and optimisation of adaptive optics performance;…

Instrumentation and Methods for Astrophysics · Physics 2018-12-19 Paulo P. Andrade , Paulo J. V. Garcia , Carlos M. Correia , Johann Kolb , Maria Inês Carvalho

The behavior of an adaptive optics (AO) system for ground-based high contrast imaging (HCI) dictates the achievable contrast of the instrument. In conditions where the coherence time of the atmosphere is short compared to the speed of the…

Instrumentation and Methods for Astrophysics · Physics 2022-05-31 Maaike A. M. van Kooten , Rebecca Jensen-Clem Sylvain Cetre , Sam Ragland , Charlotte Z. Bond , J. Fowler , Peter Wizinowich

Latency in the control loop of adaptive optics (AO) systems can severely limit performance. Under the frozen flow hypothesis linear predictive control techniques can overcome this, however identification and tracking of relevant turbulent…

Instrumentation and Methods for Astrophysics · Physics 2020-06-10 Xuewen Liu , Tim Morris , Chris Saunter , Francisco Javier de Cos Juez , Carlos González-Gutiérrez , Lisa Bardou

Carbon capture and storage (CCS) plays a crucial role in mitigating greenhouse gas emissions, particularly from industrial outputs. Using seismic monitoring can aid in an accurate and robust monitoring system to ensure the effectiveness of…

Geophysics · Physics 2025-04-01 Xinquan Huang , Fu Wang , Tariq Alkhalifah

As we deal with the effects of climate change and the increase of global atmospheric temperatures, the accurate tracking and prediction of ice layers within polar ice sheets grows in importance. Studying these ice layers reveals climate…

Machine Learning · Computer Science 2023-06-27 Benjamin Zalatan , Maryam Rahnemoonfar

Optical turbulence, driven by fluctuations of the atmospheric refractive index, poses a significant challenge to ground-based optical systems, as it distorts the propagation of light. This degradation affects both astronomical observations…

Instrumentation and Methods for Astrophysics · Physics 2026-03-26 Mary Joe Medlej , Rahul Srinivasan , Simon Prunet , Aziz Ziad , Christophe Giordano

In a recent paper the authors presented an extended study aiming at simulating the classical meteorological parameters and the optical turbulence at Dome C during the winter with the atmospherical mesoscale model Meso-NH. A statistical…

Instrumentation and Methods for Astrophysics · Physics 2010-11-29 Franck Lascaux , Elena Masciadri , Susanna Hagelin

The internal antarctic plateau revealed in the last years to be a site with interesting potentialities for the astronomical applications due to the extreme dryness and low temperatures, the typical high altitude of the plateau, the weak…

Instrumentation and Methods for Astrophysics · Physics 2015-05-14 E. Masciadri , F. Lascaux , S. Hagelin , P. Le Moigne , J. Noilhan

Usage of secondary cosmic muons to image the geological structures density distribution significantly developed during the past ten years. Recent applications demonstrate the method interest to monitor magma ascent and volcanic gas…