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Related papers: Radio Imaging With Information Field Theory

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We present a filtering technique that can be applied to individual baselines of wide-bandwidth, wide-field interferometric data to geometrically select regions on the celestial sphere that contain primary calibration sources. The technique…

Instrumentation and Methods for Astrophysics · Physics 2015-05-13 Aaron R. Parsons , Donald C. Backer

Crossmatching catalogs at different wavelengths is a difficult problem in astronomy, especially when the objects are not point-like. At radio wavelengths an object can have several components corresponding, for example, to a core and lobes.…

Instrumentation and Methods for Astrophysics · Physics 2015-05-05 Dongwei Fan , Tamás Budavári , Ray P. Norris , Andrew M. Hopkins

An interferometric fluorescent microscope and a novel theoretic image reconstruction approach were developed and used to obtain super-resolution images of live biological samples and to enable dynamic real time tracking. The tracking…

This paper presents a multilevel algorithm specifically designed for radio-interferometric imaging in astronomy. The proposed algorithm is used to solve the uSARA (unconstrained Sparsity Averaging Reweighting Analysis) formulation of this…

Optimization and Control · Mathematics 2024-03-21 Guillaume Lauga , Audrey Repetti , Elisa Riccietti , Nelly Pustelnik , Paulo Gonçalves , Yves Wiaux

Current and future radio interferometric arrays such as LOFAR and SKA are characterized by a paradox. Their large number of receptors (up to millions) allow theoretically unprecedented high imaging resolution. In the same time, the ultra…

Instrumentation and Methods for Astrophysics · Physics 2015-07-03 André Ferrari , David Mary , Rémi Flamary , Cédric Richard

The complex range of interactions between electrons and electromagnetic fields gave rise to countless scientific and technological advances. A prime example is photon-induced nearfield electron microscopy (PINEM), enabling the detection of…

We consider the probe of astrophysical signals through radio interferometers with small field of view and baselines with non-negligible and constant component in the pointing direction. In this context, the visibilities measured essentially…

Instrumentation and Methods for Astrophysics · Physics 2009-11-16 Y. Wiaux , G. Puy , Y. Boursier , P. Vandergheynst

Radio maps (RMs) provide a spatially continuous description of wireless propagation, enabling cross-layer optimization and unifying communication and sensing for integrated sensing and communications (ISAC). However, constructing…

Signal Processing · Electrical Eng. & Systems 2025-12-15 Qiming Zhang , Xiucheng Wang , Nan Cheng , Zhisheng Yin , Xiang Li

Deconvolution of the telescope Point Spread Function (PSF) is necessary for even moderate dynamic range imaging with interferometric telescopes. The process of deconvolution can be treated as a search for a model image such that the…

Astrophysics · Physics 2009-11-10 S. Bhatnagar , T. J. Cornwell

I discuss approaches to optimally remove noise from images. A generalization of Wiener filtering to Non-Gaussian distributions and wavelets is described, as well as an approach to measure the errors in the reconstructed images. We argue…

Astrophysics · Physics 2009-10-31 Ue-Li Pen

We report on a broader evaluation of statistical bootstrap resampling methods as a tool for pixel-level calibration and imaging fidelity assessment in radio interferometry. Pixel-level imaging fidelity assessment is a challenging problem,…

Instrumentation and Methods for Astrophysics · Physics 2015-05-14 Athol Kemball , Adam Martinsek , Modhurita Mitra , Hsin-Fang Chiang

Intensity interferometry (II) exploits the second-order correlation to acquire the spatial frequency information of an object, which has been used to observe distant stars since 1950s. However, due to unreliability of employed imaging…

Image and Video Processing · Electrical Eng. & Systems 2017-12-08 Wentao Wang , Qi Han , Hui Chen , Yuan Yuan , Zhuo Xu

In order to produce high dynamic range images in radio interferometry, bright extended sources need to be removed with minimal error. However, this is not a trivial task because the Fourier plane is sampled only at a finite number of…

Instrumentation and Methods for Astrophysics · Physics 2011-01-17 Sarod Yatawatta

Determining magnetic field properties in different environments of the cosmic large-scale structure as well as their evolution over redshift is a fundamental step toward uncovering the origin of cosmic magnetic fields. Radio observations…

In radio-interferometry, we recover an image from an incompletely sampled Fourier data. The de-facto standard algorithm, the Cotton-Schwab CLEAN, is iteratively switching between computing a deconvolution (minor loop) and subtracting the…

Instrumentation and Methods for Astrophysics · Physics 2026-02-04 Hendrik Müller , Mingyu Hsieh , Sanjay Bhatnagar

Measurement of interferometric parameters values is affected by phase disturbance due especially to atmospheric turbulences. Algorithms of fringe sensing, aimed at fringe parameters identification, are based on interferometric models that…

Instrumentation and Methods for Astrophysics · Physics 2009-08-27 Bonino Donata

Ultrasound images formed by delay-and-sum beamforming are plagued by artifacts that only clear up after compounding many transmissions. Some prior works pose imaging as an inverse problem. This approach can yield high image quality with few…

Signal Processing · Electrical Eng. & Systems 2024-07-03 Vincent van de Schaft , Oisín Nolan , Ruud J. G. van Sloun

Image rescaling is a commonly used bidirectional operation, which first downscales high-resolution images to fit various display screens or to be storage- and bandwidth-friendly, and afterward upscales the corresponding low-resolution…

Image and Video Processing · Electrical Eng. & Systems 2022-10-11 Mingqing Xiao , Shuxin Zheng , Chang Liu , Zhouchen Lin , Tie-Yan Liu

1D or 2D neutron imaging detectors with individual wire or strip readout using discriminators have the advantage of being able to treat several neutron impacts partially overlapping in time, hence reducing global dead time. A single neutron…

The present `state of the art' and the path to future progress in high spatial resolution imaging interferometry is reviewed. The review begins with a treatment of the fundamentals of stellar optical interferometry, the origin, properties,…

Astrophysics · Physics 2008-11-26 Swapan K Saha
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