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Related papers: P-REx II. Off-line Performance on VLTI/GRAVITY

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The James Webb Space Telescope is orders of magnitude more sensitive than any other facility across the near to mid-infrared wavelengths. Many approved programs take advantage of its highly stable point spread function (PSF) to directly…

The observable quantities in optical interferometry, which are the modulus and the phase of the complex visibility, may be corrupted by parasitic fringes superimposed on the genuine fringe pattern. These fringes are due to an interference…

Instrumentation and Methods for Astrophysics · Physics 2010-08-27 Alexis Matter , Bruno Lopez , Stéphane Lagarde , William C. Danchi , Sylvie Robbe-Dubois , Romain G. Petrov , Ramon Navarro

A crucial part of a space mission for very-long baseline interferometery (VLBI), which is the technique capable of providing the highest resolution images in astronomy, is orbit determination of the mission's space radio telescope(s). In…

Measurement of the velocity field in thermal-hydraulic experiments is of great importance for phenomena interpretation and code validation. Direct measurement employing Particle Image Velocimetry (PIV) is challenging in some multiphase…

Fluid Dynamics · Physics 2025-09-03 Xicheng Wang , YiMeng Chan , KinWing Wong , Dmitry Grishchenko , Pavel Kudinov

As the Extremely Large Telescope (ELT) approaches operational status, optimising its imaging performance is critical. A differential piston, arising from either the adaptive optics (AO) control loop, thermomechanical effects, or other…

Instrumentation and Methods for Astrophysics · Physics 2026-01-14 P. Janin-Potiron , M. Gray , B. Neichel , M. Dumont , J. -F. Sauvage , C. T. Heritier , P. Jouve , R. Fetick , T. Fusco

Visible-light long baseline interferometry holds the promise of advancing a number of important applications in fundamental astronomy, including the direct measurement of the angular diameters and oblateness of stars, and the direct…

A novel method performing 3D PTV from double frame multi-camera images is introduced. Particle velocities are estimated by following three steps. Firstly, separate particle reconstructions with a sparsity-based algorithm are performed on a…

Modeling the optical point spread function (PSF) is particularly challenging for adaptive optics (AO)-assisted observations owing to the its complex shape and spatial variations. We aim to (i) exhaustively demonstrate the accuracy of a…

Instrumentation and Methods for Astrophysics · Physics 2020-11-25 Olivier Beltramo-Martin , Romain Fétick , Benoit Neichel , Thierry Fusco

The implementation of the GRAVITY+ Adaptive Optics (GPAO) system at VLTI enables unprecedented sensitivity and stability in optical interferometry. This allows high-precision characterization of directly imaged exoplanets at medium spectral…

Instrumentation and Methods for Astrophysics · Physics 2026-03-17 J. R. Sauter , A. von Stauffenberg , G. Bourdarot , W. Brandner , F. Eisenhauer , L. Kreidberg , L. Labadie , S. Scheithauer , D. Trevascus , R. van Boekel

Continuous wavefront sensing benefits space observatories in on-orbit optical performance maintenance. To measure the phase of a wavefront, phase retrieval is an attractive technique as it uses multiple point spread function (PSF) images…

Instrumentation and Methods for Astrophysics · Physics 2024-09-17 Hyukmo Kang , Kyle Van Gorkom , Meghdoot Biswas , Daewook Kim , Ewan S. Douglas

The implementation of fringe tracking for optical interferometers is inevitable when optimal exploitation of the instrumental capacities is desired. Fringe tracking allows continuous fringe observation, considerably increasing the…

Instrumentation and Methods for Astrophysics · Physics 2015-06-04 J. Menu , G. Perrin , E. Choquet , S. Lacour

Data-driven decompositions of Particle Image Velocimetry (PIV) measurements are widely used for a variety of purposes, including the detection of coherent features (e.g., vortical structures), filtering operations (e.g., outlier removal or…

Fluid Dynamics · Physics 2020-08-26 Miguel A Mendez , David Hess , Bo B Watz , Jean-Marie Buchlin

This paper presents the Visual Optical Recognition Telemetry EXtraction (VORTEX) system for extracting and analyzing drone telemetry data from First Person View (FPV) Uncrewed Aerial System (UAS) footage. VORTEX employs MMOCR, a…

Computer Vision and Pattern Recognition · Computer Science 2025-06-10 James E. Gallagher , Edward J. Oughton

Ground-based high contrast exoplanet imaging requires state-of-the-art adaptive optics (AO) systems in order to detect extremely faint planets next to their brighter host stars. For such extreme AO systems (with high actuator count…

Earth and Planetary Astrophysics · Physics 2022-08-02 J. Fowler , Maaike A. M. Van Kooten , Rebecca Jensen-Clem

Two-wavelength adaptive optics (AO) systems sense wavefront errors using a beacon at one wavelength, while correcting for subsequent imaging or beam projection at another. Although most AO systems operate in this manner, the relevant AO…

Optics · Physics 2025-09-17 Milo Hyde , Mark Spencer , Matt Kalensky

Extreme wavefront correction is required for coronagraphs on future space telescopes to reach 1e-8 or better starlight suppression for the direct imaging and characterization of exoplanets in reflected light. Thus, a suite of wavefront…

Adaptive optics (AO) have been used to correct wavefronts to achieve diffraction limited point spread functions in a broad range of optical applications, prominently ground-based astronomical telescopes operating in near infra-red. While…

Instrumentation and Methods for Astrophysics · Physics 2018-10-03 Alexandre J. T. S. Mello , Antonin H. Bouchez , Andrew Szentgyorgyi , Marcos A. van Dam , Henrique Lupinari

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

Current post-processing techniques in high contrast imaging depend on some source of diversity between the exoplanet signal and the residual star light at that location. The two main techniques are angular differential imaging (ADI), which…

Instrumentation and Methods for Astrophysics · Physics 2016-01-20 Jared R. Males , Ruslan Belikov , Eduardo Bendek

Polarimetric interferometry is a method allowing the study of the distribution of polarized flux at diffraction-limited resolution. Its basic observable is the ratio $\mathcal{R}$ of the visibilities of the object in two orthogonal…

Instrumentation and Methods for Astrophysics · Physics 2019-02-27 Boris Safonov , Pavel Lysenko , Maria Goliguzova , Dmitry Cheryasov