HAO Colloquium - Patrick McCauley, University of Sydney

Solar Science with the Murchison Widefield Array

I will discuss recent solar science results using the Murchison Widefield Array (MWA). The MWA is a low-frequency radio interferometer in Western Australia that produces the most sensitive images of the corona to-date between 80 and 300 MHz. Solar and heliospheric science are among the telescope’s main priorities, and we have made considerable progress on these data in recent years. We have detected the weakest non-thermal radio emissions ever reported, have discovered new properties of solar radio bursts, and have recently produced the first spectropolarimetric images of the quiet Sun at these wavelengths. I will review the instrument’s capabilities and highlight recent and ongoing work across the solar collaboration. The following topics will be discussed in detail: 1) novel radio burst source motions that are interpreted in terms of strongly diverging magnetic field structures, 2) using radio bursts to probe the coronal density, and 3) a first look at the low-frequency corona in circular polarization and associated discoveries with respect to the quiet Sun, coronal holes, and active region “noise storm” sources.

Date and time: 
Wednesday, December 5, 2018 - 2:00pm to 3:00pm