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Related papers: MEM and CLEAN Imaging of VLBA Polarisation Observa…

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Extracting polarimetric information from very long baseline interferometry (VLBI) data is demanding but vital for understanding the synchrotron radiation process and the magnetic fields of celestial objects, such as active galactic nuclei…

Instrumentation and Methods for Astrophysics · Physics 2025-11-21 Jong-Seo Kim , Jakob Roth , Jongho Park , Jack D. Livingston , Philipp Arras , Torsten A. Enßlin , Michael Janssen , J. Anton Zensus , Andrei P. Lobanov

The CLEAN deconvolution algorithm has well-known limitations due to the restriction of locating point source model components on a discretized grid. In this letter we demonstrate that these limitations are even more pronounced when applying…

Instrumentation and Methods for Astrophysics · Physics 2015-06-12 M. R. Bell , N. Oppermann , A. Crai , T. A. Enßlin

We describe a maximum likelihood regularized beam deconvolution map-making algorithm for data from high resolution, polarization sensitive instruments, such as the Planck data set. The resulting algorithm, which we call PReBeaM, is…

Astrophysics · Physics 2009-11-13 Charmaine Armitage-Caplan , Benjamin D. Wandelt

The Maximum Entropy Method (MEM) is a popular data analysis technique based on Bayesian inference, which has found various applications in the research literature. While the MEM itself is well-grounded in statistics, I argue that its…

Data Analysis, Statistics and Probability · Physics 2020-11-03 Alexander Rothkopf

EGRET data are usually analysed on the basis of the Maximum-Likelihood method \cite{ma96} in a search for point sources in excess to a model for the background radiation (e.g. \cite{hu97}). This method depends strongly on the quality of the…

Astrophysics · Physics 2009-10-30 Martin Pohl

We report on recent technical developments in the front- and back-ends for the four 20 m radio telescopes of the Japanese Very-Long-Baseline Interferometry (VLBI) project, VLBI Exploration of Radio Astrometry (VERA). We present a brief…

Instrumentation and Methods for Astrophysics · Physics 2022-12-21 Yoshiaki Hagiwara , Kazuhiro Hada , Mieko Takamura , Tomoaki Oyama , Aya Yamauchi , Syunsaku Suzuki

Radio interferometric imaging has long relied on the CLEAN algorithm, valued for its speed, robustness, and integration with calibration pipelines. However, next-generation facilities such as the ngVLA, SKA, and ALMAs Wideband Sensitivity…

Instrumentation and Methods for Astrophysics · Physics 2025-09-19 Hendrik Müller

It is shown how to apply the Maximum Entropy Method (MEM) to numerical Dyson-Schwinger studies for the extraction of spectral functions of correlators from their corresponding Euclidean propagators. Differences to the application in lattice…

High Energy Physics - Phenomenology · Physics 2008-11-26 Dominik Nickel

Interferometric radio astronomy data require the effects of limited coverage in the Fourier plane to be accounted for via a deconvolution process. For the last 40 years this process, known as `cleaning', has been performed almost…

Instrumentation and Methods for Astrophysics · Physics 2016-06-15 Luke Pratley , Melanie Johnston-Hollitt

We present preliminary results of JVLA wideband full polarization observations of a sample of Active Galactic Nuclei (AGN) with very high Rotation Measure (RM) values, a sign of extreme environment. Polarization properties show a complex…

A method for making realistic estimates of the density of levels in even-even nuclei is presented making use of the Monte Carlo shell model (MCSM). The procedure follows three basic steps: (1) computation of the thermal energy with the…

Nuclear Theory · Physics 2009-10-30 W. E. Ormand

The wavelet Maximum Entropy on the Mean (wMEM) approach to the MEG inverse problem is revisited and extended to infer brain activity from full space-time data. The resulting dimensionality increase is tackled using a collection of…

Machine Learning · Statistics 2018-07-25 Marie-Christine Roubaud , Jean-Marc Lina , Julie Carrier , B Torrésani

The increased sensitivity of future radio telescopes will result in requirements for higher dynamic range within the image as well as better resolution and immunity to interference. In this paper we propose a new matrix formulation of the…

Astrophysics · Physics 2014-11-18 Chen Ben-David , Amir Leshem

Image deblurring is a notoriously challenging ill-posed inverse problem. In recent years, a wide variety of approaches have been proposed based upon regularization at the level of the image or on techniques from machine learning. We propose…

Computer Vision and Pattern Recognition · Computer Science 2020-10-22 Gabriel Rioux , Rustum Choksi , Tim Hoheisel , Pierre Marechal , Christopher Scarvelis

We develop the first algorithm able to jointly compute the maximum {\it a posteriori} estimate of the Cosmic Microwave Background (CMB) temperature and polarization fields, the gravitational potential by which they are lensed, and…

Cosmology and Nongalactic Astrophysics · Physics 2019-07-17 Marius Millea , Ethan Anderes , Benjamin D. Wandelt

Manipulating the polarization of light is highly desired for versatile applications ranging from super resolution, optical trapping, to particle acceleration. The enormous freedom in metasurface design motivates the implementation of…

Correlative light and electron microscopy is a powerful tool to study the internal structure of cells. It combines the mutual benefit of correlating light (LM) and electron (EM) microscopy information. However, the classical approach of…

Computer Vision and Pattern Recognition · Computer Science 2022-08-22 Fengjiao Ma , Rainer Kaufmann , Jaroslaw Sedzicki , Zoltán Cseresnyés , Christoph Dehio , Stephanie Hoeppener , Marc Thilo Figge , Rainer Heintzmann

Biomedical applications of plasmonic nanoparticle conjugates need control over their optical properties modulated by surface coating with stabilizing or targeting molecules often attached to or embedded in the secondary functionalization…

Optics · Physics 2025-05-01 Nikolai G. Khlebtsov , Sergey V. Zarkov

We present an imaging algorithm for polarimetric interferometric data from radio telescopes. It is based on Bayesian statistics and thereby able to provide uncertainties and to incorporate prior information such as positivity of the total…

Instrumentation and Methods for Astrophysics · Physics 2025-04-02 Philipp Arras , Jakob Roth , Martin Reinecke , Richard A. Perley , Andrei Frolov , Rüdiger Westermann , Torsten A. Enßlin