Colloquium - The nexus of Australian marsupials and broadband radio polarimetry

© Quokka image modified based on picture credited to cutestuff.co by buzzfeed and including map of the Galactic Rotation Measure foreground (Oppermann et al 2015, A&A 575, 118); all others G. Heald.

With the advent of broadband frequency coverage on modern radio interferometers - an advancement led by telescopes like the WSRT - we are entering a new age of radio polarimetry. Exquisite broadband polarimetry provides a unique view on the detailed magnetic and ionised structure within radio-emitting objects such as star-forming galaxies and AGN. We also have unique access to the time variability of magnetic structures within sources, in a manner complementary to VLBI observations.

In this presentation I will describe new, ongoing survey efforts in this direction across a wide range of frequency using Australian radio telescopes: the Murchison Widefield Array (MWA), the Australian SKA Pathfinder (ASKAP), and the Australia Telescope Compact Array (ATCA). This overview will include new data and new results, and will star a few marsupials. I will also place this fresh observational progress in the context of the extraordinary magnetism science that is now being enabled by LOFAR. The talk will conclude with some thoughts on the future of this field as we move toward the era of the SKA itself.

About the image: Clockwise from top-left: The ATCA, a happy quokka, ASKAP, and the MWA. Central image: A plot of a Faraday dispersion function (FDF) from the QUOCKA survey, which leverages detections of polarized sources made with ASKAP and follows them up with broadband polarimetric observations using the ATCA.