Cosmic magnetism

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Magnetism is one of the fundamental forces of nature. Magnetic fields are known to exist in galaxies, from the energetic nuclei that harbour super massive black holes, to the diffuse medium between the stars in the disks. Magnetic forces are known to be critically important in governing many of the phenomena that drive the evolution of galaxies, from star formation, structure formation, large-scale dynamics, and confinement and acceleration of high-energy particles. Despite their ubiquity and importance in the Universe, very little is known about the origin and evolution of cosmic magnetism. Polarization of radio emission is one of the key probes of cosmic magnetic fields. Cosmic magnetism has been identified as one of the key science goals of next generational international radio astronomy facilities that are currently under construction or planned, such as the EVLA, the Australia SKA Pathfinder and the SKA. The research described in this proposal will significantly advance our understanding of the origin, evolution and role of cosmic magnetic fields by using the world's most powerful radio telescopes to carry out large observing projects that map the polarized emission from the sky in both space and frequency. GALFACTS uses the multiple-feed horn array on the Arecibo telescope to image 40% of the sky to sensitivity five times deeper than the any previous polarization survey and with full spectral information of frequency dependence. This project will measure the polarization properties of over 1,00,000 radio sources and map the diffuse polarized emission from the interaction of magnetic fields with the interstellar medium in our Galaxy. The EVLA Deep Polarization Field will measure the faint polarized signals from disks of galaxies out to high redshifts, tracing the evolution of fields in galaxies over a significant fraction of the age of the universes. These projects combine development of advanced techniques for observing and data processing, cutting edge science, collaborations with a global network of leading researchers, and partnership with major observatories and industry - fertile environment to train young scientists who can work at the interface of advanced technologies and world-class science.