A survey of the solar data from the Murchison Widefield Array

Abstract

The Sun is a difficult radio source to study, but radio observations of the Sun carry crucial information about solar magnetic fields and coronal processes inaccessible by any other bands in the EM spectrum. Recently, instruments with capabilities matching the needs of solar radio physics have begun to become available. The Murchison Widefield Array (MWA), commissioned in mid-2013, is one such instrument which already has ∼3000 hours of solar observations. Conventional radio interferometeric imaging is very effort and computation intensive. As a part of building the ability to analyse large volumes of MWA data in an unsupervised manner, an automated imaging pipeline AIRCARS [8] has recently been developed. It routinely produces images with dynamic range between ∼1000 to ∼100,000, exceeding that of the earlier state of the art by two to three orders of magnitude. Along with the opportunity to strengthen our understanding of the Sun, every significant technological advance in solar observations has been accompanied by surprising new discoveries. This project aims to explore the potential of this newly acquired imaging capability. Given the very large computational burden of interferometric imaging, a key part of the problem is choosing the data to be analysed. This project explores a few different strategies for making this choice in an unbiased manner. We present the results from analysing some of the data so chosen using the imaging pipeline.