Seminar: Think big! The structure of the magnetic field of the Milky Way

Dominic Schnitzeler 

CSIRO

Many people understand that magnetic fields play an important role in the physics of the interstellar medium, for example in the collapse of molecular clouds, in the dynamics of the ionized gas, or as guide-wires for cosmic rays. Magnetic fields are however inherently difficult to study since they rely on polarization measurements, and the polarized intensity of most sources is typically only a few percent of their total intensity.

In my talk I will review how magnetic fields have revealed themselves, drawing on examples from the literature and from my own work. For example, by studying how the rotation measures of extragalactic sources depend on Galactic latitude I could show that most of this structure in rotation measure is produced in our own Milky Way, and not in the extragalactic sources themselves. I will conclude with an overview of ongoing and future projects to give an idea of which important questions we will try to answer in the near future.