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Related papers: Multi-scale CLEAN in hard X-ray solar imaging

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Multichannel blind deconvolution is the problem of recovering an unknown signal $f$ and multiple unknown channels $x_i$ from their circular convolution $y_i=x_i \circledast f$ ($i=1,2,\dots,N$). We consider the case where the $x_i$'s are…

Information Theory · Computer Science 2019-03-19 Yanjun Li , Yoram Bresler

The study of astronomical phenomena through ground-based observations is always challenged by the distorting effects of Earth's atmosphere. Traditional methods of post-facto image correction, essential for correcting these distortions,…

Instrumentation and Methods for Astrophysics · Physics 2024-08-14 A. Asensio Ramos

Radio astronomy is currently thriving with new large ground-based radio telescopes coming online in preparation for the upcoming Square Kilometre Array (SKA). Facilities like LOFAR, MeerKAT/SKA, ASKAP/SKA, and the future SKA-LOW bring…

Instrumentation and Methods for Astrophysics · Physics 2023-08-02 Benjamin Naoto Chiche , Julien N. Girard , Joana Frontera-Pons , Arnaud Woiselle , Jean-Luc Starck

Methods of three-dimensional deconvolution with a point-spread function as frequently employed in optical microscopy to reconstruct true three-dimensional distribution of objects are extended to holographic reconstructions. Two such schemes…

Optics · Physics 2017-08-09 Tatiana Latychevskaia , Fabian Gehri , Hans-Werner Fink

We present a natural generalization of the recent low rank + sparse matrix decomposition and consider the decomposition of matrices into components of multiple scales. Such decomposition is well motivated in practice as data matrices often…

Systems and Control · Computer Science 2016-08-04 Frank Ong , Michael Lustig

Faraday tomography (or rotation measure synthesis) is a procedure to convert linear polarization spectra into the Faraday dispersion function, which provides us with unique information of magneto-ionic media along the line of sight.…

Instrumentation and Methods for Astrophysics · Physics 2018-12-03 Kazunori Akiyama , Takuya Akahori , Yoshimitsu Miyashita , Shinsuke Ideguchi , Ryosuke Yamaguchi , Shiro Ikeda , Keitaro Takahashi

Removing the aberrations introduced by the Point Spread Function (PSF) is a fundamental aspect of astronomical image processing. The presence of noise in observed images makes deconvolution a nontrivial task that necessitates the use of…

Instrumentation and Methods for Astrophysics · Physics 2017-05-03 Samuel Farrens , Jean-Luc Starck , Fred Maurice Ngolè Mboula

This paper shows that compressed sensing realized by means of regularized deconvolution and the Finite Isotropic Wavelet Transform is effective and reliable in hard X-ray solar imaging. The method utilizes the Finite Isotropic Wavelet…

Solar and Stellar Astrophysics · Physics 2018-07-18 M. A. Duval-Poo , M. Piana , A. M. Massone

The quality of images of the Sun obtained from the ground are severely limited by the perturbing effect of the turbulent Earth's atmosphere. The post-facto correction of the images to compensate for the presence of the atmosphere require…

Solar and Stellar Astrophysics · Physics 2018-12-05 A. Asensio Ramos , J. de la Cruz Rodriguez , A. Pastor Yabar

A practical evaluation of the Multi-Scale CLEAN algorithm is presented. The data used in the comparisons are taken from The HI Nearby Galaxy Survey (THINGS). The implementation of Multi-Scale CLEAN in the CASA software package is used,…

The Reuven Ramaty High Energy Spectroscopic Solar Imager (RHESSI) uses the rotational modulation principle to observe temporally, spatially, and spectrally resolved hard X ray and gamma ray images of solar flares. In order to track the…

Astrophysics · Physics 2009-11-10 Kaspar Arzner

(arXiv abridged abstract) The current years are seeing huge developments of radio telescopes and a tremendous increase of their capabilities. Such systems make mandatory the design of more sophisticated techniques not only for transporting,…

Instrumentation and Methods for Astrophysics · Physics 2015-03-18 Arwa Dabbech , Chiara Ferrari , David Mary , Eric Slezak , Oleg Smirnov , Jonathan S. Kenyon

Recent developments in fluorescence microscopy allow capturing high-resolution 3D images over time for living model organisms. To be able to image even large specimens, techniques like multi-view light-sheet imaging record different…

Image and Video Processing · Electrical Eng. & Systems 2021-08-29 Canyu Yang , Dennis Eschweiler , Johannes Stegmaier

Magnetic Resonance Imaging (MRI) is a noninvasive imaging technique that provides exquisite soft-tissue contrast without using ionizing radiation. The clinical application of MRI may be limited by long data acquisition times; therefore, MR…

Image and Video Processing · Electrical Eng. & Systems 2020-07-10 Shen Zhao , Lee C. Potter , Kiryung Lee , Rizwan Ahmad

We derive multiscale statistics for deconvolution in order to detect qualitative features of the unknown density. An important example covered within this framework is to test for local monotonicity on all scales simultaneously. We…

Statistics Theory · Mathematics 2015-03-19 Johannes Schmidt-Hieber , Axel Munk , Lutz Duembgen

Deconvolution is the most widely used aberration correction technique in microscopy, however most techniques assume that the aberrations are the same for each point in the image, which is rarely true. Methods for tracking spatially varying…

Optics · Physics 2025-12-02 Jakub Czuchnowski , Chuan Li , Hongli Ni , Brandon Weissbourd , Jerome Mertz

An optical imaging system forms an object image by recollecting light scattered by the object. However, intact optical information of the object delivered through the imaging system is deteriorated by imperfect optical elements and unwanted…

Optics · Physics 2017-03-28 SangYun Lee , Kyeoreh Lee , Seungwoo Shin , YongKeun Park

The Atacama Large Millimeter/submillimeter Array (ALMA) is currently revolutionizing observational astrophysics. The aperture synthesis technique provides angular resolution otherwise unachievable with the conventional single-aperture…

Instrumentation and Methods for Astrophysics · Physics 2022-10-06 Łukasz Tychoniec , Fabrizia Guglielmetti , Philipp Arras , Torsten Enßlin , Eric Villard

We consider imaging of solar flares from NASA RHESSI data as a parametric imaging problem, where flares are represented as a finite collection of geometric shapes. We set up a Bayesian model in which the number of objects forming the image…

Instrumentation and Methods for Astrophysics · Physics 2018-11-26 Federica Sciacchitano , Silvio Lugaro , Alberto Sorrentino

Marine Controlled Source Electromagnetic (CSEM) is employed both in large-scale geophysical applications as well as within exploration of hydrocarbons and gas hydrates. Due to the diffusive character of the EM field only very low…

Geophysics · Physics 2022-11-08 Feng-Ping Li , Vemund Stenbekk Thorkildsen , Leiv-J Gelius , Jian-Hua Yue