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

200 papers

Optical Deflectometric Tomography (ODT) provides an accurate characterization of transparent materials whose complex surfaces present a real challenge for manufacture and control. In ODT, the refractive index map (RIM) of a transparent…

Computer Vision and Pattern Recognition · Computer Science 2013-10-31 Adriana Gonzalez , Laurent Jacques , Christophe De Vleeschouwer , Philippe Antoine

Images obtained with single-conjugate adaptive optics (AO) show spatial variation of the point spread function (PSF) due to both atmospheric anisoplanatism and instrumental aberrations. The poor knowledge of the PSF across the field of view…

One of the aims of next generation optical interferometric instrumentation is to be able to make use of information contained in the visibility phase to construct high dynamic range images. Radio and optical interferometry are at the two…

The Five-hundred-meter Aperture Spherical radio Telescope (FAST) is the world's largest single-dish radio telescope. Its large reflecting surface achieves unprecedented sensitivity but is prone to damage, such as dents and holes, caused by…

Computer Vision and Pattern Recognition · Computer Science 2022-12-20 Jianan Li , Shenwang Jiang , Liqiang Song , Peiran Peng , Feng Mu , Hui Li , Peng Jiang , Tingfa Xu

Various methods have been introduced to measure the orbital angular momentum (OAM) of light, from fork holograms to Dove prism interferometers, from tilted lenses to triangular apertures - each with their own benefits and limitations. Here…

Partial frequency redistribution (PRD), describing the formation of the line profile, has negligible observational effects for optical depths smaller than ~10^3, at the resolving power of most current instruments. However, when the spectral…

Earth and Planetary Astrophysics · Physics 2015-05-27 Roxana E. Lupu , Paul D. Feldman , Stephan R. McCandliss , Darrell F. Strobel

Two-wavelength adaptive optics (AO) systems sense turbulence-induced wavefront distortions using an artificial beacon or natural guidestar at one wavelength, while correcting and possibly transmitting at another. Although most existing AO…

Optics · Physics 2025-05-02 Milo W. Hyde , Matthew Kalensky , Mark F. Spencer

The success of ground-based instruments for high contrast exoplanet imaging depends on the degree to which adaptive optics (AO) systems can mitigate atmospheric turbulence. While modern AO systems typically suffer from millisecond time lags…

Instrumentation and Methods for Astrophysics · Physics 2019-09-13 Rebecca Jensen-Clem , Charlotte Z. Bond , Sylvain Cetre , Eden McEwen , Peter Wizinowich , Sam Ragland , Dimitri Mawet , James Graham

Scaling up interferometry to 8m collectors should smooth-out the optical piston perturbations and allow a slow fringe tracker to obtain high precision correction on faint targets. In practice, the GRAVITY fringe tracker still observes high…

Commonly used wavefront sensors, the Shack Hartmann wavefront sensor and the pyramid wavefront sensor, for example, have large dynamic range or high sensitivity, trading one regime for the other. A new type of wavefront sensor is being…

Instrumentation and Methods for Astrophysics · Physics 2022-08-19 Meghan Farris O'Brien , Sebastiaan Y. Haffert , Joseph D. Long , Lauren Schatz , Jared R. Males , Kyle Van Gorkom , Alex Rodack

Spaceborne gravitational-wave observatories utilize a postprocessing technique known as time-delay interferometry (TDI) to reduce the otherwise overwhelming laser frequency noise by around 8 orders of magnitude. While, in its traditional…

Instrumentation and Methods for Astrophysics · Physics 2025-06-11 Kohei Yamamoto , Jan Niklas Reinhardt , Olaf Hartwig

In order for telescopes to obtain good and precise images they need to see through atmospheric turbulence. To accomplish this and compensate for atmospheric turbulence we use Adaptive Optics technologies. In this thesis we analyze the…

Instrumentation and Methods for Astrophysics · Physics 2023-10-13 Cesar Laguna

Focal ratio degradation (FRD) is a major contributor to throughput and light loss in a fibre spectroscopic telescope system. We combine the guided mode theory in geometric optics and a well-known model, power distribution model (PDM), to…

Instrumentation and Methods for Astrophysics · Physics 2019-12-25 Yunxiang Yan , Gang Wang , Weimin Sun , A-Li Luo , Zhenyu Ma , Jian Li , Shuqing Wang

The attitude dynamics of aircraft and spacecraft exhibit significantly nonlinear behaviour. In spacecraft, torque is generated through reaction wheels and control moment gyros. In aircraft, torque is generated using lift on control…

Dynamical Systems · Mathematics 2026-04-15 Aleksandr Talitckii , Matthew Peet

Astronomers usually need the highest angular resolution possible, but the blurring effect of diffraction imposes a fundamental limit on the image quality from any single telescope. Interferometry allows light collected at widely-separated…

Instrumentation and Methods for Astrophysics · Physics 2015-05-20 John D. Monnier , Ronald J. Allen

Deflection of light along the optical path is a major source of image degradation for ground-based telescopes. Methods have been developed to measure upper atmospheric seeing based on models of the turbulence in the atmosphere, but due to…

Instrumentation and Methods for Astrophysics · Physics 2025-08-04 Meghan A. Marangola , Elana K. Urbach , Christopher W. Stubbs

PHASECam is the fringe tracker for the Large Binocular Telescope Interferometer (LBTI). It is a near-infrared camera which is used to measure both tip/tilt and fringe phase variations between the two adaptive optics (AO) corrected apertures…

Instrumentation and Methods for Astrophysics · Physics 2020-07-30 Erin R. Maier , Phil Hinz , Denis Defrère , Paul Grenz , Elwood Downey , Steve Ertel , Katie Morzinski , Ewan S. Douglas

This study introduces an experimental teaching method that employs optic fiber interferometry (OFI) to investigate forced vibration phenomena. It is designed for undergraduate physics majors with foundational mechanics and optics training…

Physics Education · Physics 2025-04-22 Mingyuan Wang , Manli Zhou , Hengda Ji , Tao Lan

This paper is the third part of a trilogy dealing with the principles, performance and limitations of what I named "Telescope-Interferometers" (TIs). The basic idea consists in transforming one telescope into a Wavefront Error (WFE) sensing…

Optics · Physics 2011-05-17 Francois Henault