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Related papers: The non-coplanar baselines effect in radio interfe…

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We present a new algorithm to perform wide-field radio interferometric image reconstruction, with exact non-coplanar correction, that scales to big-data. This algorithm allows us to image 2 billion visibilities on 50 nodes of a computing…

Instrumentation and Methods for Astrophysics · Physics 2019-03-20 Luke Pratley , Jason D. McEwen

With the development of modern radio interferometers, wide-field continuum surveys have been planned and undertaken, for which accurate wide-field imaging methods are essential. Based on the widely-used W-stacking method, we propose a new…

Instrumentation and Methods for Astrophysics · Physics 2023-05-01 Haoyang Ye , Steve F. Gull , Sze M. Tan , Bojan Nikolic

We generalize Gaussian/Wuppertal smearing in order to produce non-spherical wave functions. We show that we can achieve a reduction in the noise-to-signal ratio for correlation functions of certain hadrons at non-zero momentum, while at the…

High Energy Physics - Lattice · Physics 2015-06-11 Michele Della Morte , Benjamin Jaeger , Thomas Rae , Hartmut Wittig

Incorporating wide-field considerations in interferometric imaging is of increasing importance for next-generation radio telescopes. Compressed sensing techniques for interferometric imaging have been extended to wide fields recently,…

Instrumentation and Methods for Astrophysics · Physics 2011-08-29 J. D. McEwen , Y. Wiaux

On an example of the open nonlinear electrodynamic system - transverse non-homogeneous, isotropic, nonmagnetic, linearly polarized, nonlinear (a Kerr-like dielectric nonlinearity) dielectric layer, the algorithms of solution of the…

Computational Physics · Physics 2007-05-23 V. V. Yatsyk

After several generations of interferometers in radioastronomy, wide-field imaging at high angular resolution is today a major goal for trying to match optical wide-field performances. All the radio-interferometric, wide-field imaging…

Instrumentation and Methods for Astrophysics · Physics 2015-05-18 Jérôme Pety , Nemesio J. Rodriguez-Fernandez

When a plane electromagnetic wave impinges upon a diffraction grating or other periodic structures, reflected and transmitted waves propagate away from the structure in different radiation channels. A diffraction anomaly occurs when the…

Computational Physics · Physics 2022-10-05 Zitao Mai , Ya Yan Lu

An obstacle to the detection of redshifted 21cm emission from the epoch of reionization (EoR) is the presence of foregrounds which exceed the cosmological signal in intensity by orders of magnitude. We argue that in principle it would be…

The Australia Telescope Compact Array and the Very Large Array are currently being upgraded to operate with wide bandwidths; interferometers dedicated to the measurement of cosmic microwave background anisotropies are being designed with…

Astrophysics · Physics 2009-11-10 Ravi Subrahmanyan

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

If the optical system of a telescope is perturbed from rotational symmetry, the Zernike wavefront aberration coefficients describing that system can be expressed as a function of position in the focal plane using spin-weighted Zernike…

Instrumentation and Methods for Astrophysics · Physics 2018-02-19 Stephen M. Kent

In this work we present a new WENO b-spline based quasi-interpolation algorithm. The novelty of this construction resides in the application of the WENO weights to the b-spline functions, that are a partition of unity, instead to the…

Numerical Analysis · Mathematics 2023-08-14 Sergio Amat , David Levin , Juan Ruiz-Álvarez , Dionisio F. Yáñez

Interferometric Synthetic Aperture Radar (InSAR) Imaging methods are usually based on algorithms of match-filtering type, without considering the scene's characteristic, which causes limited imaging quality. Besides, post-processing steps…

Signal Processing · Electrical Eng. & Systems 2022-10-07 Xu Zhan , Xiaoling Zhang , Shunjun Wei , Jun Shi

We study the impact of the spread spectrum effect in radio interferometry on the quality of image reconstruction. This spread spectrum effect will be induced by the wide field-of-view of forthcoming radio interferometric telescopes. The…

Instrumentation and Methods for Astrophysics · Physics 2013-01-31 Laura Wolz , Filipe B. Abdalla , Rafael E. Carrillo , Yves Wiaux , Jason D. McEwen

Context: Low-frequency radio observations are heavily impacted by the ionosphere, where dispersive delays can outpace even instrumental clock offsets, posing a serious calibration challenge. Especially below 100 MHz, phase unwrapping…

Instrumentation and Methods for Astrophysics · Physics 2025-10-03 C. M. Cordun , M. A. Brentjens , H. K. Vedantham , M. Mevius

The paper reviews progress in imaging in radio interferometry for the period 1993-1996. Unlike an optical telescope, the basic measurements of a radio interferometer (correlations between antennas) are indirectly related to a sky brightness…

Astrophysics · Physics 2007-05-23 R. J. Sault , T. A. Oosterloo

The development of new phased array systems in radio astronomy, as the low frequency array (LOFAR) and the square kilometre array (SKA), formed of a large number of small and flexible elementary antennas, has led to significant challenges.…

Radio interferometer arrays such as HERA consist of many close-packed dishes arranged in a regular pattern, giving rise to a large number of `redundant' baselines with the same length and orientation. Since identical baselines should see an…

Cosmology and Nongalactic Astrophysics · Physics 2021-06-30 Samir Choudhuri , Philip Bull , Hugh Garsden

Large radio telescopes in the 21st century such as the Low-Frequency Array (LOFAR) or the Murchison Widefield Array (MWA) make use of phased aperture arrays of antennas to achieve superb survey speeds. The Square Kilometer Array low…

Instrumentation and Methods for Astrophysics · Physics 2017-12-06 Ha Bui-Van , Christophe Craeye , Eloy de Lera Acedo