De-distorting ionospheric effects in the image plane

The Earth's ionosphere refracts radio waves incident on an interferometer, resulting in shifts to the measured positions of radio sources. We present a method to smoothly remove these shifts and restore sources to their reference positions, in both the catalogue and image domains. The method is...

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Bibliographic Details
Main Authors: Hurley-Walker, Natasha, Hancock, Paul
Format: Journal Article
Published: 2018
Online Access:http://hdl.handle.net/20.500.11937/71045
Description
Summary:The Earth's ionosphere refracts radio waves incident on an interferometer, resulting in shifts to the measured positions of radio sources. We present a method to smoothly remove these shifts and restore sources to their reference positions, in both the catalogue and image domains. The method is applicable to instruments and ionospheric weather such that all antennas see the same ionosphere. The method is generalisable to repairing any sparsely-sampled vector field distortion to some input data. The code is available under the Academic Free License1from <a href="https://github.com/nhurleywalker/fits_warp">https://github.com/nhurleywalker/fits_warp</a>.