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Spatially resolved observations of molecular line emission have the potential to yield unique constraints on the nature of turbulence within protoplanetary disks. Using a combination of local non-ideal magnetohydrodynamic simulations and…

Solar and Stellar Astrophysics · Physics 2015-08-19 Jacob B. Simon , A. Meredith Hughes , Kevin M. Flaherty , Xue-Ning Bai , Philip J. Armitage

Vertically stable in density, stratified-water conditions 'SW' exist in the deep Mediterranean Sea that are characterized by temperature differences of 0.0002-0.01degrC over 125 m above a flat seafloor. These result in a mean buoyancy…

Atmospheric and Oceanic Physics · Physics 2026-01-09 Hans van Haren

This work presents a rigorous statistical and geometric framework for analyzing turbulence-impacted beam propagation and image topology with results obtained using a PMMA slab. The approach models beam intensity distributions as…

Optics · Physics 2025-10-02 Shouvik Sadhukhan , C. S. Narayanamurthy

We propose design of a low-cost passive scintillometer that measures the strength of optical turbulence by analyzing scintillation in the image of a straight edge between the two areas of uniform, but distinct brightness. Two theoretical…

Optics · Physics 2021-11-24 Mikhail Charnotskii

The transverse spatial modes of light offer a large state-space with interesting physical properties. For exploiting it in future long-distance experiments, spatial modes will have to be transmitted over turbulent free-space links. Numerous…

We present results from our two year study of ground-layer turbulence as seen through the 6.5-meter Magellan Telescopes at Las Campanas Observatory. The experiment consists of multiple, moderate resolution, Shack-Hartmann wavefront sensors…

Astrophysics · Physics 2009-11-11 A. Athey , S. Shectman , M. Phillips , J. Thomas-Osip

We present first results of a simultaneous atmospheric turbulence measurement campaign at the Calar Alto (Spain) 1.23m and 3.5m telescopes. A SCIDAR instrument and the Calar Alto Adaptive Optics system ALFA were used at the 1.23m and 3.5m…

Astrophysics · Physics 2007-05-23 A. R. Weiss , S. Hippler , M. E. Kasper , N. J. Wooder , J. C. Quartel

Turbulence is a fundamental parameter in models of grain growth during the early stages of planet formation. As such, observational constraints on its magnitude are crucial. Here we self-consistently analyze ALMA CO(2-1), SMA CO(3-2), and…

Earth and Planetary Astrophysics · Physics 2018-04-11 Kevin M. Flaherty , A. Meredith Hughes , Richard Teague , Jacob B. Simon , Sean M. Andrews , David J. Wilner

We report the measurement of a large optical reflection matrix (RM) of a highly disordered medium. Incident optical fields onto a turbid sample are controlled by a spatial light modulator, and the corresponding fields reflected from the…

Optics · Physics 2019-08-17 Hyeonseung Yu , Jung-Hoon Park , YongKeun Park

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

Accurate prediction of atmospheric optical turbulence in localized environments is essential for estimating the performance of free-space optical systems. Macro-meteorological models developed to predict turbulent effects in one environment…

Atmospheric and Oceanic Physics · Physics 2023-10-30 Christopher Jellen , Charles Nelson , John Burkhardt , Cody Brownell

We present the development, tests and first results of the second generation Low Layer Scidar (LOLAS-2). This instrument constitutes a strongly improved version of the prototype Low Layer Scidar, which is aimed at the measurement of optical…

Instrumentation and Methods for Astrophysics · Physics 2016-06-17 R. Avila , C. A. Zuniga , J. J. Tapia-Rodriguez , L. J. Sanchez , I. Cruz-Gonzalez , J. L. Aviles , O. Valdes-Hernandez , E. Carrasco

The present study extends the analysis of turbulence-affected beam statistics through a manifold-based statistical framework that unifies probabilistic modeling with geometric interpretation. The spatial intensity distributions, distorted…

Optics · Physics 2025-10-22 Shouvik Sadhukhan , C. S. Narayanamurthy

Here we propose an optical method that use phase data of a laser beam obtained from Shack-Hartmann sensor to estimate both inner and outer scales of turbulence. The method is based on the sequential analysis of normalized correlation…

Atmospheric and Oceanic Physics · Physics 2015-06-03 V. A. Kulikov , M. S. Andreeva , A. V. Koryabin , V. I. Shmalhausen

The scattering of light observed through the turbid underwater channel is often regarded as the leading challenge when designing underwater electro-optical imaging systems. There have been many approaches to address the effects of…

Optics · Physics 2018-04-17 Chensheng Wu , Robert Lee , Christopher C. Davis

Umbral dots (UDs) were observed using the 1.6 meter solar telescope. Achieved conventional diffraction limit in the TiO 705.68 nm spectral line used was 0.1". The 418 UDs were analysed. Median diameter was 0.5'' and median intensity…

Solar and Stellar Astrophysics · Physics 2015-06-03 Aleksandra Andic

The circumgalactic medium (CGM) of nearby star-forming galaxies shows clear indications of OVI absorption accompanied by little to no detectable NV absorption. This unusual spectral signature, accompanied by highly non-uniform absorption…

Astrophysics of Galaxies · Physics 2020-07-01 Edward Buie , William J. Gray , Evan Scannapieco , Mohammadtaher Safarzadeh

This paper reports turbulent boundary layer measurements made over open-cell reticulated foams with varying pore size and thickness, but constant porosity ($\epsilon \approx 0.97$). The foams were flush-mounted into a cutout on a flat…

Fluid Dynamics · Physics 2018-03-14 Christoph Efstathiou , Mitul Luhar

Optical fibres constitute an exceptional sensing platform. However, standard fibres present an inherent sensing challenge: they confine light by design to an inner core. Consequently, nearly all distributed fibre sensors are restricted to…

Optics · Physics 2018-11-21 Gil Bashan , Hilel Hagai Diamandi , Yosef London , Eyal Preter , Avi Zadok

Radio emission propagating over an Earth-pulsar line of sight provides a unique probe of the intervening ionized interstellar medium (ISM). Variations in the integrated electron column density along this line of sight, or dispersion measure…

High Energy Astrophysical Phenomena · Physics 2020-04-08 M. T. Lam , T. J. W. Lazio , T. Dolch , M. L. Jones , M. A. McLaughlin , D. R. Stinebring , M. Surnis
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