Efficient correction for both direction-dependent and baseline-dependent effects in interferometric imaging: An A-stacking framework
Artikel i vetenskaplig tidskrift, 2015

A general framework is presented for modeling direction-dependent effects that are also baseline-dependent, as part of the calibration and imaging process. Within this framework such effects are represented as a parametric linear model in which basis functions account for direction dependence, whereas expansion coefficients account for the baseline dependence. This separation enables the use of a multiple fast Fourier transform-based implementation of the forward calculation (sky to visibility) in a manner similar to the W-stacking solution for non-coplanar baselines, and offers a potential improvement in computational efficiency in scenarios where the gridding operation in a convolution-based approach to direction-dependent effects may be too costly. Two novel imaging approaches that are possible within this framework are also presented.

methods: analytical

techniques: image processing

methods: numerical

Författare

A. Young

Universiteit Stellenbosch

S. J. Wijnholds

Netherlands Institute for Radio Astronomy (ASTRON)

Tobia Carozzi

Chalmers, Rymd- och geovetenskap, Onsala rymdobservatorium

Rob Maaskant

Chalmers, Signaler och system, Kommunikationssystem, informationsteori och antenner, Antennsystem

Marianna Ivashina

Chalmers, Signaler och system, Kommunikationssystem, informationsteori och antenner, Antennsystem

D. B. Davidson

Universiteit Stellenbosch

Astronomy and Astrophysics

0004-6361 (ISSN) 1432-0746 (eISSN)

Vol. 577 Art. no. A56- A56

Ämneskategorier

Fusion, plasma och rymdfysik

DOI

10.1051/0004-6361/201425492