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Related papers: Direction-Dependent Faraday Synthesis

200 papers

There is evidence that magnetized material along the line of sight to distant quasars is detectable in the polarization properties of the background sources. The polarization properties appear to be correlated with the presence of…

Astrophysics of Galaxies · Physics 2016-10-05 Kwang Seong Kim , Simon J. Lilly , Francesco Miniati , M. L. Bernet , Rainer Beck , S. P. O'Sullivan , B. M. Gaensler

Faraday tomography through broadband polarimetry can provide crucial information on magnetized astronomical objects, such as quasars, galaxies, or galaxy clusters. However, the limited wavelength coverage of the instruments requires that we…

Instrumentation and Methods for Astrophysics · Physics 2022-08-17 Suchetha Cooray , Tsutomu T. Takeuchi , Shinsuke Ideguchi , Takuya Akahori , Yoshimitsu Miyashita , Keitaro Takahashi

Depolarization of diffuse radio synchrotron emission is classified in terms of wavelength-independent and wavelength-dependent depolarization in the context of regular magnetic fields and of both isotropic and anisotropic turbulent magnetic…

Astrophysics of Galaxies · Physics 2014-09-05 Carl Shneider , Marijke Haverkorn , Andrew Fletcher , Anvar Shukurov

While current multi-frame restoration methods combine information from multiple input images using 2D alignment techniques, recent advances in novel view synthesis are paving the way for a new paradigm relying on volumetric scene…

Computer Vision and Pattern Recognition · Computer Science 2023-04-06 Thomas Tanay , Aleš Leonardis , Matteo Maggioni

Polarization calibration of interferometric observations is a costly procedure and, in some cases (e.g., a limited coverage of parallactic angle for the calibrator), it may not be possible to be performed. To avoid this worst-case scenario…

Instrumentation and Methods for Astrophysics · Physics 2023-04-05 E. Albentosa-Ruiz , I. Marti-Vidal

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

In this paper we present a detailed analysis of the Faraday depth (FD) spectrum and its clean components obtained through the application of the commonly used technique of Faraday rotation measure synthesis to analyze spectro-polarimetric…

Astrophysics of Galaxies · Physics 2019-11-21 Aritra Basu , Andrew Fletcher , S. A. Mao , Blakesley Burkhart , Rainer Beck , Dominic Schnitzeler

Direction-dependent instrumental polarisation introduces wide-field polarimetric aberrations and limits the dynamic range of low-frequency interferometric images. We therefore provide a detailed two-dimensional analysis of the Giant…

Instrumentation and Methods for Astrophysics · Physics 2014-07-03 J. S. Farnes

A direct consequence of Faraday rotation is that the polarized radio sky does not resemble the total intensity sky at long wavelengths. We analyze G137+7, which is undetectable in total intensity but appears as a depolarization feature. We…

We present an analysis of the polarization of compact radio sources from six pointings of the Westerbork Synthesis Radio Telescope (WSRT) at 350 MHz with 35% coverage in lambda^2. After correcting for the off-axis instrumental polarization…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-27 Damon Farnsworth , Lawrence Rudnick , Shea Brown

We describe a new technique for probing galactic and extragalactic 2D and 3D magnetic field distribution using gradients of polarized synchrotron emission. The fluctuations of magnetic field are elongated along the ambient magnetic field.…

Astrophysics of Galaxies · Physics 2018-10-10 A. Lazarian , Ka Ho Yuen

(abridged) We run a Faraday structure determination data challenge to benchmark the currently available algorithms including Faraday synthesis (previously called RM synthesis in the literature), wavelet, compressive sampling and…

Observational study of galactic magnetic fields is limited by projected observables. Comparison with numerical simulations is helpful to understand the real structures, and observational visualization of numerical data is an important task.…

Astrophysics of Galaxies · Physics 2018-11-14 Mami Machida , Takuya Akahori , Kenji Nakamura , Hiroyuki Nakanishi , Marijke Haverkorn

(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

The process of wide-field synthesis imaging is explored, with the aim of understanding the implications of variable, polarised primary beams for forthcoming Epoch of Reionisation experiments. These experiments seek to detect weak signatures…

Instrumentation and Methods for Astrophysics · Physics 2012-06-05 Daniel A. Mitchell , Randall B. Wayth , Gianni Bernardi , Lincoln J. Greenhill , Stephen M. Ord

Radio synthesis imaging is dependent upon deconvolution algorithms to counteract the sparse sampling of the Fourier plane. These deconvolution algorithms find an estimate of the true sky brightness from the necessarily incomplete sampled…

Astrophysics · Physics 2009-11-13 T. J. Cornwell

We introduce DiffRF, a novel approach for 3D radiance field synthesis based on denoising diffusion probabilistic models. While existing diffusion-based methods operate on images, latent codes, or point cloud data, we are the first to…

Computer Vision and Pattern Recognition · Computer Science 2023-03-28 Norman Müller , Yawar Siddiqui , Lorenzo Porzi , Samuel Rota Bulò , Peter Kontschieder , Matthias Nießner

Since its formulation by Hamaker et al., the radio interferometer measurement equation (RIME) has provided a rigorous mathematical basis for the development of novel calibration methods and techniques, including various approaches to the…

Instrumentation and Methods for Astrophysics · Physics 2011-02-07 Oleg M. Smirnov

In image deconvolution problems, the diagonalization of the underlying operators by means of the FFT usually yields very large speedups. When there are incomplete observations (e.g., in the case of unknown boundaries), standard…

Computer Vision and Pattern Recognition · Computer Science 2016-08-31 Miguel Simões , Luis B. Almeida , José Bioucas-Dias , Jocelyn Chanussot