English
Related papers

Related papers: Optical Turbulence Characterization at LAMOST Site…

200 papers

Phase referencing is a standard calibration procedure in radio interferometry. It allows to detect weak sources by using quasi-simultaneous observations of closeby sources acting as calibrators. Therefore, it is assumed that, for each…

Instrumentation and Methods for Astrophysics · Physics 2011-01-25 I. Marti-Vidal , J. C. Guirado , S. Jimenez-Monferrer , J. M. Marcaide

We present first results of a new instrument, the Generalized Differential Image Motion Monitor (GDIMM), aiming at monitoring parameters of the optical turbulence (seeing, isoplanatic angle, coherence time and outer scale). GDIMM is based…

Instrumentation and Methods for Astrophysics · Physics 2018-11-20 Eric Aristidi , Yan Fantei-Caujolle , Aziz Ziad , Cécile Dimur , Julien Chabé , Baptiste Roland

We report results of a two-year campaign of measurements, during arctic winter darkness, of optical turbulence in the atmospheric boundary-layer above the Polar Environment Atmospheric Laboratory in northern Ellesmere Island (latitude +80…

Instrumentation and Methods for Astrophysics · Physics 2015-06-15 P. Hickson , R. Gagne , T. Pfrommer , E. Steinbring

In this paper I investigate what factors -- both observational and physical -- can change the measured slope of the observed 21cm HI power spectrum. The following effects can make the observed turbulence appear two dimensional rather than…

Astrophysics · Physics 2007-05-23 A. H. Minter

This paper investigates the problem of estimating three stellar atmospheric physical parameters and thirteen elemental abundances for medium-resolution spectra from Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST). Typical…

Solar and Stellar Astrophysics · Physics 2023-12-27 Xiangru Li , Xiaoyu Zhang , Shengchun Xiong , Yulong Zheng , Hui Li

Substellar companions such as exoplanets and brown dwarfs exhibit changes in brightness arising from top-of-atmosphere inhomogeneities, providing insights into their atmospheric structure and dynamics. This variability can be measured in…

Optical aberrations and instrument resolution can affect the observed morphological properties of features in the solar atmosphere. However, little work has been done to study the effects of spatial resolution on the dynamical processes…

Solar and Stellar Astrophysics · Physics 2026-01-06 M. Berretti , M. Stangalini , D. B. Jess , S. Jafarzadeh , S. D. T. Grant , G. Verth , V. Fedun , G. Chambers , F. Berrilli

Terahertz (THz) wireless communications have the potential to realize ultra-high-speed and secure data transfer with miniaturized devices for unmanned aerial vehicle (UAV) communications. The atmospheric turbulence due to random airflow…

Systems and Control · Electrical Eng. & Systems 2024-01-29 Weijun Gao , Chong Han , Zhi Chen

In this work we present an observational technique and a detailed analysis of the stellar interferograms produced by three bright stars: Betelgeuse, Rigel and Sirius. It is shown that the atmospheric turbulence is responsible for the…

Instrumentation and Methods for Astrophysics · Physics 2024-06-13 P. Rodriguez-Ovalle , A. Mendi-Martos , A . Angulo-Manzanas , I. Reyes-Rodriguez , M. Perez-Arrieta , M. A. Illarramendi , A. Sanchez-Lavega

Adaptive optics will almost completely remove the effects of atmospheric turbulence at 10 microns on the Extremely Large Telescope (ELT) generation of telescopes. In this paper, we observationally confirm that the next most important…

Instrumentation and Methods for Astrophysics · Physics 2010-03-26 Andrew Skemer , Philip Hinz , William Hoffmann , Laird Close , Sarah Kendrew , Richard Mathar , Remko Stuik , Thomas Greene , Charles Woodward , Michael Kelley

Adaptive Optics at mid-IR wavelengths has long been seen as either not necessary or easy. The impact of atmospheric turbulence on the performance of 8-10 meter class telescopes in the mid-IR is relatively small compared to other performance…

Instrumentation and Methods for Astrophysics · Physics 2015-05-14 R. Stuik , L. Jolissaint , S. Kendrew , S. Hippler , B. Brandl , L. Venema

We present an analysis of the science image quality obtained on the twin 6.5 metre Magellan telescopes over a 1.5 year period, using images of ~10^5 stars. We find that the telescopes generally obtain significantly better image quality than…

Instrumentation and Methods for Astrophysics · Physics 2015-05-18 David J. E. Floyd , Jo Thomas-Osip , Gabriel Prieto

We investigate the dynamic response of flexible aircraft in low-altitude atmospheric turbulence. To this end, three turbulence models of increasing fidelity, namely, the one-dimensional von K{\'a}rm{\'a}n model, the two-dimensional Kaimal…

Fluid Dynamics · Physics 2020-03-27 Georgios Deskos , Alfonso del Carre , Rafael Palacios

This paper analyses 3.5 years of site testing data obtained at Dome C, Antarctica, based on measurements obtained with three DIMMs located at three different elevations. Basic statistics of the seeing and the isoplanatic angle are given, as…

Instrumentation and Methods for Astrophysics · Physics 2015-05-13 E. Aristidi , E. Fossat , A. Agabi , D. Mekarnia , F. Jeanneaux , E. Bondoux , Z. Challita , A. Ziad , J. Vernin , H. Trinquet

Strong turbulence conditions create amplitude aberrations through the effects of near-field diffraction. When integrated over long optical path lengths, amplitude aberrations (seen as scintillation) can nullify local areas in the recorded…

Instrumentation and Methods for Astrophysics · Physics 2020-12-30 Justin R. Crepp , Stanimir O. Letchev , Sam J. Potier , Joshua H. Follansbee , Nicholas T. Tusay

Optical beams propagating through atmospheric turbulence undergo spatiotemporal intensity fluctuations that deviate significantly from an ideal Gaussian profile. In this work, we present a unified theoretical and experimental framework for…

Optics · Physics 2026-03-10 Shouvik Sadhukhan , C. S. Narayanamurthy

Propagation of optical vortex beamlet (OVB) in turbulent atmospheric environment is studied theoretically by normalized models. Our simulation shows that optical vortex beamlet is superior to traditional Gaussian beam in terms of…

Optics · Physics 2016-12-09 YuanYao Lin

The low infrared background and high atmospheric transparency are the principal advantages of Antarctic Plateau sites for astronomy. However, the poor seeing (between one and three arcseconds) negates much of the sensitivity improvements…

Astrophysics · Physics 2009-11-07 James P. Lloyd , Ben R. Oppenheimer , James R. Graham

Turbulence is a key element of the dynamics of astrophysical fluids, including those of interstellar medium, clusters of galaxies and circumstellar regions. Turbulent motions induce Doppler shifts of observable emission and absorption lines…

Astrophysics · Physics 2009-03-27 A. Chepurnov , A. Lazarian

Data from the Palomar Testbed Interferometer, with a baseline length of 110 m and an observing wavelength of $2.2 \mu{\rm m}$, were used to derive information on atmospheric turbulence on 64 nights in 1999. The measured two-aperture…

Astrophysics · Physics 2009-11-06 R. P. Linfield , M. M. Colavita , B. F. Lane