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arXiv · 1101.0620

First Spectroscopic Imaging Observations of the Sun at Low Radio Frequencies with the Murchison Widefield Array Prototype

Divya Oberoi·Lynn D. Matthews·Iver H. Cairns·David Emrich·Vasili Lobzin·Colin J. Lonsdale·Edward H. Morgan·T. Prabu·Harish Vedantham·Randall B. Wayth·Andrew Williams·Christopher Williams·Stephen M. White·G. Allen·Wayne Arcus·David Barnes·Leonid Benkevitch·Gianni Bernardi·Judd D. Bowman·Frank H. Briggs·John D. Bunton·Steve Burns·Roger C. Cappallo·M. A. Clark·Brian E. Corey·M. Dawson·David DeBoer·A. De Gans·Ludi deSouza·Mark Derome·R. G. Edgar·T. Elton·Robert Goeke·M. R. Gopalakrishna·Lincoln J. Greenhill·Bryna Hazelton·David Herne·Jacqueline N. Hewitt·P. A. Kamini·David L. Kaplan·Justin C. Kasper·Rachel Kennedy·Barton B. Kincaid·Jonathan Kocz·R. Koeing·Errol Kowald·Mervyn J. Lynch·S. Madhavi·Stephen R. McWhirter·Daniel A. Mitchell·Miguel F. Morales·A. Ng·Stephen M. Ord·Joseph Pathikulangara·Alan E. E. Rogers·Anish Roshi·Joseph E. Salah·Robert J. Sault·Antony Schinckel·N. Udaya Shankar·K. S. Srivani·Jamie Stevens·Ravi Subrahmanyan·D. Thakkar·Steven J. Tingay·J. Tuthill·Annino Vaccarella·Mark Waterson·Rachel L. Webster·Alan R. Whitney
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Abstract

We present the first spectroscopic images of solar radio transients from the prototype for the Murchison Widefield Array (MWA), observed on 2010 March 27. Our observations span the instantaneous frequency band 170.9-201.6 MHz. Though our observing period is characterized as a period of `low' to `medium' activity, one broadband emission feature and numerous short-lived, narrowband, non-thermal emission features are evident. Our data represent a significant advance in low radio frequency solar imaging, enabling us to follow the spatial, spectral, and temporal evolution of events simultaneously and in unprecedented detail. The rich variety of features seen here reaffirms the coronal diagnostic capability of low radio frequency emission and provides an early glimpse of the nature of radio observations that will become available as the next generation of low frequency radio interferometers come on-line over the next few years.

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Divya Oberoi, Lynn D. Matthews, Iver H. Cairns, David Emrich, Vasili Lobzin, Colin J. Lonsdale, Edward H. Morgan, T. Prabu, Harish Vedantham, Randall B. Wayth, Andrew Williams, Christopher Williams, Stephen M. White, G. Allen, Wayne Arcus, David Barnes, Leonid Benkevitch, Gianni Bernardi, Judd D. Bowman, Frank H. Briggs, John D. Bunton, Steve Burns, Roger C. Cappallo, M. A. Clark, Brian E. Corey, M. Dawson, David DeBoer, A. De Gans, Ludi deSouza, Mark Derome, R. G. Edgar, T. Elton, Robert Goeke, M. R. Gopalakrishna, Lincoln J. Greenhill, Bryna Hazelton, David Herne, Jacqueline N. Hewitt, P. A. Kamini, David L. Kaplan, Justin C. Kasper, Rachel Kennedy, Barton B. Kincaid, Jonathan Kocz, R. Koeing, Errol Kowald, Mervyn J. Lynch, S. Madhavi, Stephen R. McWhirter, Daniel A. Mitchell, Miguel F. Morales, A. Ng, Stephen M. Ord, Joseph Pathikulangara, Alan E. E. Rogers, Anish Roshi, Joseph E. Salah, Robert J. Sault, Antony Schinckel, N. Udaya Shankar, K. S. Srivani, Jamie Stevens, Ravi Subrahmanyan, D. Thakkar, Steven J. Tingay, J. Tuthill, Annino Vaccarella, Mark Waterson, Rachel L. Webster, Alan R. Whitney. 2011-01-03. First Spectroscopic Imaging Observations of the Sun at Low Radio Frequencies with the Murchison Widefield Array Prototype. https://doi.org/10.1088/2041-8205/728/2/l27

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