View Item 

Power spectrum analysis of ionospheric fluctuations with the Murchison Widefield Array

Access Status
Open access
Authors
Loi, S.
Trott, Cathryn
Murphy, T.
Cairns, I.
Bell, M.
Hurley-Walker, Natasha
Morgan, John
Lenc, E.
Offringa, A.
Feng, L.
Hancock, P.
Kaplan, D.
Kudryavtseva, N.
Bernardi, G.
Bowman, J.
Briggs, F.
Cappallo, R.
Corey, B.
Deshpande, A.
Emrich, D.
Gaensler, B.
Goeke, R.
Greenhill, L.
Hazelton, B.
Johnston-Hollitt, M.
Kasper, J.
Kratzenberg, E.
Lonsdale, C.
Lynch, Mervyn
Mcwhirter, S.
Mitchell, D.
Morales, M.
Morgan, E.
Oberoi, D.
Ord, S.
Prabu, T.
Rogers, A.
Roshi, A.
Shankar, N.
Srivani, K.
Subrahmanyan, R.
Tingay, Steven
Waterson, M.
Wayth, Randall
Webster, R.
Whitney, A.
Williams, A.
Williams, C.
Date
2015
Type
Journal Article

Metadata
Show full item record
Citation
Loi, S. and Trott, C. and Murphy, T. and Cairns, I. and Bell, M. and Hurley-Walker, N. and Morgan, J. et al. 2015. Power spectrum analysis of ionospheric fluctuations with the Murchison Widefield Array. Radio Science. 50 (7): pp. 574-597.
Source Title
Radio Science
DOI
ISSN
School
Curtin Institute of Radio Astronomy (Physics)
Funding and Sponsorship
Remarks

An edited version of this paper was published by AGU. Copyright 2015 American Geophysical Union

URI
Collection
Abstract

Low-frequency, wide field-of-view (FOV) radio telescopes such as the Murchison Widefield Array (MWA) enable the ionosphere to be sampled at high spatial completeness. We present the results of the first power spectrum analysis of ionospheric fluctuations in MWA data, where we examined the position offsets of radio sources appearing in two data sets. The refractive shifts in the positions of celestial sources are proportional to spatial gradients in the electron column density transverse to the line of sight. These can be used to probe plasma structures and waves in the ionosphere. The regional (10–100 km) scales probed by the MWA, determined by the size of its FOV and the spatial density of radio sources (typically thousands in a single FOV), complement the global (100–1000 km) scales of GPS studies and local (0.01–1 km) scales of radar scattering measurements. Our data exhibit a range of complex structures and waves. Some fluctuations have the characteristics of traveling ionospheric disturbances, while others take the form of narrow, slowly drifting bands aligned along the Earth's magnetic field.