Journal article

Ionospheric Modelling using GPS to Calibrate the MWA. I: Comparison of First Order Ionospheric Effects between GPS Models and MWA Observations

BS Arora, J Morgan, SM Ord, SJ Tingay, N Hurley-Walker, M Bell, G Bernardi, NDR Bhat, F Briggs, JR Callingham, AA Deshpande, KS Dwarakanath, A Ewall-Wice, L Feng, B-Q For, P Hancock, BJ Hazelton, L Hindson, D Jacobs, M Johnston-Hollitt Show all

PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF AUSTRALIA | CAMBRIDGE UNIV PRESS | Published : 2015

Abstract

We compare first-order (refractive) ionospheric effects seen by the MWA with the ionosphere as inferred from GPS data. The first-order ionosphere manifests itself as a bulk position shift of the observed sources across an MWA field of view. These effects can be computed from global ionosphere maps provided by GPS analysis centres, namely the CODE. However, for precision radio astronomy applications, data from local GPS networks needs to be incorporated into ionospheric modelling. For GPS observations, the ionospheric parameters are biased by GPS receiver instrument delays, among other effects, also known as receiver DCBs. The receiver DCBs need to be estimated for any non-CODE GPS station us..

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Grants

Awarded by US National Science Foundation


Awarded by Australian Research Council


Awarded by US Air Force Office of Scientific Research


Awarded by Centre for All-sky Astrophysics (an Australian Research Council Centre of Excellence)


Awarded by Victoria University of Wellington from New Zealand Ministry of Economic Development


Awarded by Victoria University of Wellington from IBM Shared University Research Grant


Awarded by Div Atmospheric & Geospace Sciences


Funding Acknowledgements

The authors wish to thank Anthony Willis from National Research Council of Canada for the valuable discussions. This scientific work makes use of the MRO, operated by Commonwealth Scientific and Industrial Research Organisation (CSIRO). We acknowledge the Wajarri Yamatji people as the traditional owners of the Observatory site. Support for the MWA comes from the US National Science Foundation (grants AST-0457585, PHY-0835713, CAREER-0847753, and AST-0908884), the Australian Research Council (LIEF grants LE0775621 and LE0882938), the US Air Force Office of Scientific Research (grant FA9550-0510247), and the Centre for All-sky Astrophysics (an Australian Research Council Centre of Excellence funded by grant CE110001020). Support is also provided by the Smithsonian Astrophysical Observatory, the MIT School of Science, the Raman Research Institute, the Australian National University, and the Victoria University of Wellington (via grant MED-E1799 from the New Zealand Ministry of Economic Development and an IBM Shared University Research Grant). The Australian Federal government provides additional support via the CSIRO, National Collaborative Research Infrastructure Strategy, Education Investment Fund, and the Australia India Strategic Research Fund, and Astronomy Australia Limited, under contract to Curtin University. We acknowledge the iVEC Petabyte Data Store, the Initiative in Innovative Computing and the CUDA Center for Excellence sponsored by NVIDIA at Harvard University, and the International Centre for Radio Astronomy Research (ICRAR), a Joint Venture of Curtin University and The University of Western Australia, funded by the Western Australian State government.