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Related papers: P-REx: The Piston Reconstruction Experiment for In…

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For sensitive optical interferometry, it is crucial to control the evolution of the optical path difference (OPD) of the wavefront between the individual telescopes of the array. The OPD between a pair of telescopes is induced by…

Instrumentation and Methods for Astrophysics · Physics 2021-12-28 Saavidra Perera , Jörg-Uwe Pott , Julien Woillez , Martin Kulas , Wolfgang Brandner , Sylvestre Lacour , Felix Widmann

Current and future ground-based interferometers require knowledge of the atmospheric time constant t_0, but this parameter has diverse definitions. Moreover, adequate techniques for monitoring t_0 still have to be implemented. We derive a…

Astrophysics · Physics 2016-08-31 A. Kellerer , A. Tokovinin

Temporal fluctuations of the atmospheric piston are critical for interferometers as they determine their sensitivity. We characterize an instrumental set-up, termed the piston scope, that aims at measuring the atmospheric time constant,…

Astrophysics · Physics 2009-11-13 A. Kellerer , M. Sarazin , T. Butterley , R. Wilson

Tau-REx (Tau Retrieval of Exoplanets) is a novel, fully Bayesian atmospheric retrieval code custom built for extrasolar atmospheres. In Waldmann et al. (2015) the transmission spectroscopic case was introduced, here we present the emission…

Earth and Planetary Astrophysics · Physics 2015-10-28 Ingo P. Waldmann , Marco Rocchetto , Giovanna Tinetti , Emma J. Barton , Sergey N. Yurchenko , Jonathan Tennyson

Interferometric measurements with arrays of radio antennas are a powerful and widely used technique in astronomy. Recently, this technique has been revisited for the reconstruction of extensive air showers [1]. This radio-interferometric…

Instrumentation and Methods for Astrophysics · Physics 2022-12-16 Felix Schlüter , Tim Huege

Reconstructing the structure of thin films and multilayers from measurements of scattered X-rays or neutrons is key to progress in physics, chemistry, and biology. However, finding all structures compatible with reflectometry data is…

Physics-informed methods have gained a great success in analyzing data with partial differential equation (PDE) constraints, which are ubiquitous when modeling dynamical systems. Different from the common penalty-based approach, this work…

Methodology · Statistics 2024-10-08 Tongyu Li , Fang Yao

Many adaptive optics systems operate by measuring the distortion of the wavefront in one wavelength range and performing the scientific observations in a second, different wavelength range. One common technique is to measure wavefront…

Astrophysics · Physics 2009-11-07 Henry G. Roe

Fusion experiments rely heavily on the measurement of the line-integrated electron density by interferometry for density feed-back control. In recent years the discharge length has increased dramatically and is continuing to rise, resulting…

Instrumentation and Detectors · Physics 2019-11-14 K. J. Brunner , J. Knauer , J. Meineke , M. Stern , M. Hirsch , B. Kursinski , R. C. Wolf , the W7-X team

Observations close to the diffraction limit, with high Strehl ratios from Adaptive Optics (AO)-assisted instruments mounted on ground-based telescopes are a reality and will become even more widespread with the next generation instruments…

Instrumentation and Methods for Astrophysics · Physics 2023-10-23 Matteo Simioni , Carmelo Arcidiacono , Andrea Grazian , Marco Gullieuszik , Elisa Portaluri , Benedetta Vulcani , Roland Wagner , Anita Zanella

This paper develops a unifying framework for signal reconstruction from interferometric measurements that is broadly applicable to various applications of interferometry. In this framework, the problem of signal reconstruction in…

Information Theory · Computer Science 2017-07-03 Davood Mardani , George K. Atia , Ayman F. Abouraddy

Reproduction experiments of radial pyroxene (RP) chondrules were carried out using an Ar-$\mathrm{H_2}$ or Ar gas-jet levitation system in a reducing atmosphere in order to simulate chondrule formation in the protoplanetary disk. The…

Earth and Planetary Astrophysics · Physics 2024-01-23 Kana Watanabe , Tomoki Nakamura , Tomoyo Morita

The use of Fourier methods in wave-front reconstruction can significantly reduce the computation time for large telescopes with a high number of degrees of freedom. However, Fourier algorithms for discrete data require a rectangular data…

Instrumentation and Methods for Astrophysics · Physics 2017-06-07 Charlotte Z. Bond , Carlos M. Correia , Jean-François Sauvage , Benoit Neichel , Thierry Fusco

A new class of implicit-explicit (IMEX) methods combined with a p-adaptive mixed finite element formulation is proposed to simulate the diffusion of reacting species. Hierarchical polynomial functions are used to construct an…

Time-resolved CT is an advanced measurement technique that has been widely used to observe dynamic objects, including periodically varying structures such as hearts, lungs, or hearing structures. To reconstruct these objects from CT…

Medical Physics · Physics 2025-06-05 Qianwei Qu , Christian M. Schlepütz , Marco Stampanoni

We generalize the technique of fringe-rate filtering, whereby visibilities measured by a radio interferometer are re-weighted according to their temporal variation. As the Earth rotates, radio sources traverse through an interferometer's…

Instrumentation and Methods for Astrophysics · Physics 2016-03-21 Aaron R. Parsons , Adrian Liu , Zaki S. Ali , Carina Cheng

Radio interferometry is the current method of choice for deep space astronomy, but in the past few decades optical techniques have become increasingly common. This research seeks to characterize the performance of aperture masking…

Instrumentation and Methods for Astrophysics · Physics 2020-08-28 Kyle Morgenstein

The Segmented Planar Imaging Detector for Electro-Optical Reconnaissance (SPIDER) is an optical interferometric imaging device that aims to offer an alternative to the large space telescope designs of today with reduced size, weight and…

Instrumentation and Methods for Astrophysics · Physics 2024-01-17 Matthijs Mars , Marta M. Betcke , Jason D. McEwen

We introduce an interferometric technique for passive time-of-flight imaging and depth sensing at micrometer axial resolutions. Our technique uses a full-field Michelson interferometer, modified to use sunlight as the only light source. The…

Computer Vision and Pattern Recognition · Computer Science 2023-03-29 Alankar Kotwal , Anat Levin , Ioannis Gkioulekas

Positron Emission Tomography (PET) image reconstruction is inherently challenged by Poisson noise and physical degradation factors, which are further exacerbated in limited-angle acquisitions. While deep learning methods demonstrate…

Computer Vision and Pattern Recognition · Computer Science 2026-05-11 Rüveyda Yilmaz , Yuli Wu , Johannes Stegmaier , Volkmar Schulz
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