Power spectrum analysis of ionospheric fluctuations with the Murchison Widefield Array
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.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Jul 01, 2015
- Source ID
- 10.1002/2015rs005711
Entities
People
- A. A. Deshpande
- A. E. E. Rogers
- A. R. Offringa
- A. R. Whitney
- A. Roshi
- A. Williams
- B. E. Corey
- B. J. Hazelton
- B. M. Gaensler
- C. J. Lonsdale
- Cathryn M. Trott
- Cleo Loi
- Cyril L. Williams
- D. A. Mitchell
- D. Emrich
- D. L. Kaplan
- Divya Oberoi
- E. Kratzenberg
- Emil Lenc
- Eric R. Morgan
- F. Briggs
- Gregorio Bernardi
- Iver H. Cairns
- J. C. Kasper
- J. D. Bowman
- John Morgan
- K. S. Srivani
- L. J. Greenhill
- Lin Feng
- M. F. Morales
- M. J. Lynch
- M. Johnston‐hollitt
- M. Waterson
- Martin Bell
- N. Kudryavtseva
- N. Udaya Shankar
- Natasha Hurley‐walker
- P. J. Hancock
- R. B. Wayth
- R. Goeke
- R. J. Cappallo
- R. L. Webster
- R. Subrahmanyan
- S. J. Tingay
- S. M. Ord
- S. R. Mcwhirter
- T. Prabu
- Tara Murphy
Organizations
- ARC Centre of Excellence for All-Sky Astrophysics
- ASTRON
- Air Force Office of Scientific Research
- Arizona State University
- Australian National University
- Australian Research Council
- Curtin University
- Massachusetts Institute of Technology
- National Centre for Radio Astrophysics
- National Radio Astronomy Observatory
- National Science Foundation
- Raman Research Institute
- Rhodes University
- Square Kilometre Array
- University of Melbourne
- University of Michigan
- University of Sydney
- University of Toronto
- University of Washington
- University of Wisconsin–Milwaukee
- Victoria University of Wellington