Polarization Sky Survey of the Universe’s Magnetism

Principal Investigators: Naomi McClure-Griffiths (ANU), George Heald (CSIRO) and Craig Anderson (ANU)
Understanding the Universe is impossible without understanding magnetic fields. Magnetic fields are key to the non-thermal Universe, yet it is unclear how large-scale magnetic fields are generated and maintained. POSSUM will use radio source polarization, in particular the technique of rotation measure (RM) synthesis, to perform a wide-field survey that will yield a grid of RMs over a substantial fraction of the sky. The science outcomes of POSSUM will revolutionise our understanding of the ordered components of the Milky Way’s magnetic field, test dynamo and other models of magnetic field generation in galaxies and clusters, and carry out a comprehensive census of magnetic fields as a function of redshift in galaxies, active galactic nuclei, galaxy clusters and the intergalactic medium. POSSUM will develop its primary data products through post-processing of continuum data collected commensally with the EMU and WALLABY surveys. In areas of the sky covered by both EMU and WALLABY, POSSUM will be able to develop particularly precise RMs. More information: POSSUM webpage