English
Related papers

Related papers: Reference Optical Turbulence and Wind Profiles for…

200 papers

In this article, we review the interdisciplinary techniques (borrowed from physics, mathematics, statistics, machine-learning, etc.) and methodological framework that we have used to understand climate systems, which serve as examples of…

Data Analysis, Statistics and Probability · Physics 2024-05-29 Alka Yadav , Sourish Das , Anirban Chakraborti

We have investigated the temporal variability and statistics of the "instantaneous" Strehl ratio. The observations were carried out with the 3.63-m AEOS telescope equipped with a high-order adaptive optics system. In this paper Strehl ratio…

Astrophysics · Physics 2009-11-13 Szymon Gladysz , Julian C. Christou , L. William Bradford , Lewis C. Roberts

High penetration of renewable energy sources and the increasing share of stochastic loads require the explicit representation of uncertainty in tools such as the optimal power flow (OPF). Current approaches follow either a linearized…

Systems and Control · Computer Science 2020-07-24 Andreas Venzke , Lejla Halilbasic , Uros Markovic , Gabriela Hug , Spyros Chatzivasileiadis

Outflows are observed in a variety of astrophysical sources. Remarkably, ultra-fast ($v\geq 0.1c$), outflows in the UV and X-ray bands are often seen in AGNs. Depending on their energy and mass outflow rate, respectively $\dot{E}_{out},…

High Energy Astrophysical Phenomena · Physics 2020-01-15 A. Luminari , F. Tombesi , E. Piconcelli , F. Nicastro , K. Fukumura , D. Kazanas , F. Fiore , L. Zappacosta

One of the key-points for the future developments of the multiconjugate adaptive optics for the astronomy is the availability of the correction for a large fraction of the sky. The sky coverage represents one of the limits of the existing…

Instrumentation and Methods for Astrophysics · Physics 2014-11-20 Carmelo Arcidiacono , Emiliano Diolaiti , Roberto Ragazzoni , Jacopo Farinato , Elise Vernet

We present a new method to retrieve molecular abundances and temperature profiles from exoplanet atmosphere photometry and spectroscopy. We run millions of 1D atmosphere models in order to cover the large range of allowed parameter space,…

Earth and Planetary Astrophysics · Physics 2014-11-20 N. Madhusudhan , S. Seager

Radar Wind Profilers (RWP) are well-established instruments for the probing of the atmospheric boundary layer, with the immense advantage of long-range and all-weather operation capability. One of their main limitations, however, is a…

Atmospheric and Oceanic Physics · Physics 2022-12-07 Baptiste Domps , Julien Marmain , Charles-Antoine Guérin

Performance of Free Space Optical (FSO) communication system is affected by atmospheric turbulences and pointing errors. These effects can easily be mitigated by adapting natural system parameters such as wavelength. In this paper,…

Signal Processing · Electrical Eng. & Systems 2019-02-27 Mohammad Ali Amirabadi

Orbital angular momentum of photons is an intriguing system for the storage and transmission of quantum information, but it is rapidly degraded by atmospheric turbulence. We explore the ability of adaptive optics to compensate for this…

Quantum Physics · Physics 2016-12-09 Jose Raul Gonzalez Alonso , Todd Brun

Wavefront estimation is an essential component of adaptive optics where the goal is to recover the underlying phase from its Fourier magnitude. While this may sound identical to classical phase retrieval, wavefront estimation faces more…

Signal Processing · Electrical Eng. & Systems 2025-04-15 Nicholas Chimitt , Ali Almuallem , Qi Guo , Stanley H. Chan

We present results from the first year of a campaign to characterize and monitor the optical turbulence profile at the SAAO Sutherland observing station in South Africa. A MASS-DIMM (MultiAperture Scintillation Sensor - Differential Image…

Instrumentation and Methods for Astrophysics · Physics 2013-10-29 Laure Catala , Steven M. Crawford , David A. H. Buckley , Tim Pickering , Richard Wilson , Tim Butterley , Harry Shepherd , Fred Marang , Patrick Matshaya , Chantal Fourie

We apply the proper orthogonal decomposition (POD) to large eddy simulation data of a wind turbine wake in a turbulent atmospheric boundary layer. The turbine is modeled as an actuator disk. Our analyis mainly focuses on the question…

Fluid Dynamics · Physics 2015-03-11 David Bastine , Björn Witha , Matthias Wächter , Joachim Peinke

A modeling paradigm is developed to augment predictive models of turbulence by effectively utilizing limited data generated from physical experiments. The key components of our approach involve inverse modeling to infer the spatial…

Computational Engineering, Finance, and Science · Computer Science 2016-11-08 Anand Pratap Singh , Shivaji Medida , Karthik Duraisamy

The planning and operation of renewable energy, especially wind power, depend crucially on accurate, timely, and high-resolution weather information. Coarse-grid global numerical weather forecasts are typically downscaled to meet these…

The performance of an adaptive optics (AO) system on a 100m diameter ground based telescope working in the visible range of the spectrum is computed using an analytical approach. The target Strehl ratio of 60% is achieved at 0.5um with a…

Astrophysics · Physics 2009-10-31 M. Le Louarn , N. Hubin , M. Sarazin , A. Tokovinin

For the simulation of anisoplanatic optical turbulence, split-step propagation is the gold standard. Within the context of the degradations being limited to phase distortions, one instead may focus on generating the phase realizations…

Optics · Physics 2023-05-17 Nicholas Chimitt , Stanley H. Chan

We describe a new method involving wavelet transforms for deriving the wind velocity associated with atmospheric turbulence layers from Generalized SCIDAR measurements. The algorithm analyses the cross-correlation of a series of…

Astrophysics · Physics 2016-08-30 B. Garcia-Lorenzo , J. J. Fuensalida

Previous analytical and numerical work shows that the generalized interacting stellar winds model can explain the observed bipolar shapes of planetary nebulae very well. However, many circumstellar nebulae have a multipolar or…

Astrophysics · Physics 2007-05-23 Erik-Jan Rijkhorst , Vincent Icke , Garrelt Mellema

The heating of the solar wind is a key to understand its dynamics and acceleration process. The observed radial decrease of proton temperature in the solar wind is slow compared to the adiabatic prediction and it is thought to be caused by…

Space Physics · Physics 2026-03-03 Victor Montagud-Camps , Roland Grappin , Andrea Verdini

Data-driven turbulence modeling has been considered an effective method for improving the prediction accuracy of Reynolds-averaged Navier-Stokes equations. Related studies aimed to solve the discrepancy of traditional turbulence modeling by…

Fluid Dynamics · Physics 2020-10-19 Yuhui Yin , Pu Yang , Yufei Zhang , Haixin Chen , Song Fu