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Current optical interferometers are affected by unknown turbulent phases on each telescope. In the field of radio-interferometry, the self-calibration technique is a powerful tool to process interferometric data with missing phase…

Optics · Physics 2009-11-13 Serge Meimon , Laurent M. Mugnier , Guy Le Besnerais

The wavelength dependence of atmospheric refraction causes elongation of finite-bandwidth images along the elevation vector, which produces spurious signals in weak gravitational lensing shear measurements unless this atmospheric dispersion…

Instrumentation and Methods for Astrophysics · Physics 2015-06-04 Andrés A. Plazas , Gary M. Bernstein

The phase structure function accumulated by two parallel rays after transmission through a layer of turbulent air is best known by a proportionality to the 5/3rd power of the lateral distance in the aperture, derived from an isotropic…

Instrumentation and Methods for Astrophysics · Physics 2011-03-01 Richard J. Mathar

Aleatoric uncertainty is an intrinsic property of ill-posed inverse and imaging problems. Its quantification is vital for assessing the reliability of relevant point estimates. In this paper, we propose an efficient framework for…

Image and Video Processing · Electrical Eng. & Systems 2020-01-16 Chen Zhang , Bangti Jin

We consider an error model for phased array with gain errors and phase errors, with errors dependent on the phase applied and the antenna index. Under this model, we propose an algorithm for measuring the errors by selectively turning on…

Signal Processing · Electrical Eng. & Systems 2021-07-21 Joyson Sebastian , Pranav Dayal , Kee-Bong Song , Walid AliAhmad

Space-based coronagraphs for future earth-like planet detection will require focal plane wavefront control techniques to achieve the necessary contrast levels. These correction algorithms are iterative and the control methods require an…

Instrumentation and Methods for Astrophysics · Physics 2015-06-11 Tyler D. Groff , N. Jeremy Kasdin

A discrete spherical harmonics method is developed for the radiative transfer problem in inhomogeneous polarized planar atmosphere illuminated at the top by a collimated sunlight while the bottom reflects the radiation. The method expands…

Instrumentation and Methods for Astrophysics · Physics 2018-02-07 Romuald Tapimo , Hervé Thierry Tagne Kamdem , David Yemele

We describe a gyroscope that measures rotation based on the effects of the rotation on the polarization of light. Rotation induces a differential phase shift in the propagation of left- and right-circularly polarized light and this phase…

We combine single- and two-photon interference procedures for characterizing any multi-port linear optical interferometer accurately and precisely. Accuracy is achieved by estimating and correcting systematic errors that arise due to…

Quantum Physics · Physics 2016-03-03 Ish Dhand , Abdullah Khalid , He Lu , Barry C. Sanders

Measurements of transverse profiles using Ionization Profile Monitors (IPMs) for high brightness beams are affected by the electromagnetic field of the beam. This interaction may cause a distortion of the measured profile shape despite…

Accelerator Physics · Physics 2019-05-22 Dominik Vilsmeier , Mariusz Sapinski , Rahul Singh

The predictions of parameteric property models and their uncertainties are sensitive to systematic errors such as inconsistent reference data, parametric model assumptions, or inadequate computational methods. Here, we discuss the…

Chemical Physics · Physics 2017-08-14 Jonny Proppe , Markus Reiher

The Epoch of Reionization (EoR) and Cosmic Dawn (CD) are pivotal stages during the first billion years of the universe, exerting a significant influence on the development of cosmic structure. The detection of the redshifted 21-cm signal…

Cosmology and Nongalactic Astrophysics · Physics 2025-10-14 Anshuman Tripathi , Abhirup Datta , Aishrila Mazumder , Suman Majumdar

Passive radar has key advantages over its active counterpart in terms of cost and stealth. In this paper, we address passive radar imaging problem by interferometric inversion using a spectral estimation method with a priori information…

Signal Processing · Electrical Eng. & Systems 2022-12-06 Samia Kazemi , Bariscan Yonel , Birsen Yazici

The LOw Frequency ARray (LOFAR) is a next-generation radio telescope which uses thousands of stationary dipoles to observe celestial phenomena. These dipoles are grouped in various 'stations' which are centred on the Netherlands with…

Solar and Stellar Astrophysics · Physics 2019-08-13 Richard A. Fallows , Ashish Asgekar , Mario M Bisi , Andrew R. Breen , Sander ter Veen

Laser guide stars with adaptive optics allow astronomical image correction in the absence of a natural guide star. Single guide star systems with a star created in the earth's sodium layer can be used to correct the wavefront in the near…

Astrophysics · Physics 2009-11-11 S. Rabien , F. Eisenhauer , R. Genzel , R. I. Davies , T. Ott

The detection of B-modes in the CMB polarization pattern is a major issue in modern cosmology and must therefore be handled with analytical methods that produce reliable results. We describe a method that uses the frequency dependency of…

Published analyses of very long baseline interferometry (VLBI) data for the sources included in the third International Celestial Reference Frame (ICRF3) catalog have revealed object-specific, excess astrometric variability and…

Astrophysics of Galaxies · Physics 2024-11-27 Valeri V. Makarov , Phil Cigan , David Gordon , Megan C. Johnson , Christopher DiLullo , Sébastien Lambert

We have upgraded IRCAL, the near-infrared science camera of the Lick Observatory adaptive optics system, to add a dual-channel imaging polarimetry mode. This mode uses an optically contacted YLF (LiYF_4) Wollaston prism to provide…

Astrophysics · Physics 2009-11-13 Marshall D. Perrin , James R. Graham , James P. Lloyd

A method is described intended for distributed calibration of a probe microscope scanner consisting in a search for a net of local calibration coefficients (LCCs) in the process of automatic measurement of a standard surface, whereby each…

Materials Science · Physics 2018-12-13 Rostislav V. Lapshin

We present the results of an experiment to image the interacting binary star beta Lyrae with data from the Navy Prototype Optical Interferometer (NPOI), using a differential phase technique to correct for the effects of the instrument and…

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