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Atom interferometers are sensitive to a wide range of forces by encoding their signals in interference patterns of matter waves. To estimate the magnitude of these forces, the underlying phase shifts they imprint on the atoms must be…

In radio interferometry, observed visibilities are intrinsically sampled at some interval in time and frequency. Modern interferometers are capable of producing data at very high time and frequency resolution; practical limits on storage…

Instrumentation and Methods for Astrophysics · Physics 2016-07-15 M. T. Atemkeng , O. M. Smirnov , C. Tasse , G. Foster , J. Jonas

Instrumental aberrations strongly limit high-contrast imaging of exoplanets, especially when they produce quasistatic speckles in the science images. With the help of recent advances in deep learning, we have developed in previous works an…

Instrumentation and Methods for Astrophysics · Physics 2022-11-14 Maxime Quesnel , Gilles Orban de Xivry , Olivier Absil , Gilles Louppe

Imaging in radio astronomy is usually carried out with a single-dish radio telescope doing a raster scan of a region of the sky or with an interferometer that samples the visibility function of the sky brightness. Mosaic observations are…

Instrumentation and Methods for Astrophysics · Physics 2019-06-12 Urvashi Rau , Nikhil Naik , Timothy Braun

We consider the high-resolution imaging problem of 3D point source image recovery from 2D data using a method based on point spread function (PSF) engineering. The method involves a new technique, recently proposed by S.~Prasad, based on…

Signal Processing · Electrical Eng. & Systems 2019-06-13 Chao Wang , Raymond Chan , Mila Nikolova , Robert Plemmons , Sudhakar Prasad

Accurate astrometry and photometry of saturated and coronagraphic point spread functions (PSFs) are fundamental to both ground- and space-based high contrast imaging projects. For ground-based adaptive optics imaging, differential…

Astrophysics · Physics 2008-11-26 C. Marois , D. Lafreniere , B. Macintosh , R. Doyon

The past decade has brought many innovations in optical design for 3D super-resolution imaging of point-like emitters, but these methods often focus on single-emitter localization precision as a performance metric. Here, we propose a simple…

Optics · Physics 2022-09-28 James M. Jusuf , Matthew D. Lew

Single-shot volumetric fluorescence (SVF) imaging offers a significant advantage over traditional imaging methods that require scanning across multiple axial planes as it can capture biological processes with high temporal resolution. The…

We present a detailed analysis of the point spread function (PSF) of JWST NIRCam imaging in eight filters: F070W, F115W, F150W, F200W, F277W, F356W, F444W, and F480M, using publicly available data. Spatial variations in the PSF FWHM…

Astrophysics of Galaxies · Physics 2023-04-28 Ming-Yang Zhuang , Yue Shen

Modern radio telescopes, such as the Square Kilometre Array (SKA), will probe the radio sky over large fields-of-view, which results in large w-modulations of the sky image. This effect complicates the relationship between the measured…

Instrumentation and Methods for Astrophysics · Physics 2017-07-14 Arwa Dabbech , Laura Wolz , Luke Pratley , Jason D. McEwen , Yves Wiaux

W projection is a commonly-used approach to allow interferometric imaging to be accelerated by Fast Fourier Transforms (FFTs), but it can require a huge amount of storage for convolution kernels. The kernels are not separable, but we show…

Instrumentation and Methods for Astrophysics · Physics 2016-01-27 Bruce Merry

We present a two-channel deconvolution method that decomposes images into a parametric point-source channel and a pixelized extended-source channel. Based on the central idea of the deconvolution algorithm proposed by Magain, Courbin & Sohy…

Instrumentation and Methods for Astrophysics · Physics 2016-04-27 N. Cantale , F. Courbin , M. Tewes , P. Jablonka. , G. Meylan

One of the problems often encountered in X-ray mirror manufacturing is setting proper manufacturing tolerances to guarantee an angular resolution - often expressed in terms of Point Spread Function (PSF) - as needed by the specific science…

Optics · Physics 2015-09-17 D. Spiga , L. Raimondi

Video synthetic aperture radar (SAR) is attracting more attention in recent years due to its abilities of high resolution, high frame rate and advantages in continuous observation. Generally, the polar format algorithm (PFA) is an efficient…

Computer Vision and Pattern Recognition · Computer Science 2024-01-22 Jiawei Jiang , Yinwei Li , Shaowen Luo , Ping Li , Yiming Zhu

High quality imaging usually requires bulky and expensive lenses to compensate geometric and chromatic aberrations. This poses high constraints on the optical hash or low cost applications. Although one can utilize algorithmic…

Image and Video Processing · Electrical Eng. & Systems 2021-08-20 Xiu Li , Jinli Suo , Weihang Zhang , Xin Yuan , Qionghai Dai

The sparse layouts of radio interferometers result in an incomplete sampling of the sky in Fourier space which leads to artifacts in the reconstructed images. Cleaning these systematic effects is essential for the scientific use of…

Instrumentation and Methods for Astrophysics · Physics 2023-07-27 Kevin Schmidt , Felix Geyer , Stefan Fröse , Paul-Simon Blomenkamp , Marcus Brüggen , Francesco de Gasperin , Dominik Elsässer , Wolfgang Rhode

Ground-based solar observations enable unprecedented spatial, spectral, and temporal resolution of the lower solar atmosphere, yet Earths turbulent atmosphere imposes significant limitations, requiring advanced post-facto image…

Solar and Stellar Astrophysics · Physics 2026-03-06 Christoph Schirninger , Robert Jarolim , Astrid M. Veronig , Matthias Rempel , Friedrich Wöger

The Point Spread Function (PSF) is a key figure of merit for specifying the angular resolution of optical systems and, as the demand for higher and higher angular resolution increases, the problem of surface finishing must be taken…

Instrumentation and Methods for Astrophysics · Physics 2016-10-04 K. Tayabaly , D. Spiga , G. Sironi , R. Canestrari , M. Lavagna , G. Pareschi

Medical ultrasound provides images which are the spatial map of the tissue echogenicity. Unfortunately, an ultrasound image is a low-quality version of the expected Tissue Reflectivity Function (TRF) mainly due to the non-ideal Point Spread…

Image and Video Processing · Electrical Eng. & Systems 2021-09-28 Sobhan Goudarzi , Hassan Rivaz

We introduce the first end-to-end learning-based solution to near-field Photometric Stereo (PS), where the light sources are close to the object of interest. This setup is especially useful for reconstructing large immobile objects. Our…

Computer Vision and Pattern Recognition · Computer Science 2022-03-31 Daniel Lichy , Soumyadip Sengupta , David W. Jacobs