Observations show that galaxies have magnetic fields with a component that is coherent over a large fraction of the galaxy, with defined field strength and coherence scale. Understanding the origin of these fields is one of the more challenging questions of modern astrophysics. There are currently two pictures: a bottom-up (astrophysical) one, generating the seed field on smaller scales, and a top-down (cosmological) version, generating the seed field prior to galaxy formation on scales that are now large. This project aims to answer several relevant questions: (i) How and when was the magnetic field generated? (ii) How does it evolve during the expansion of the universe? (iii) Can the amplitude and statistical properties of this seed magnetic field explain the properties of the observed magnetic fields in large-scale structures? (iv) Is the seed magnetic field detectable through cosmological observations? And if so, (v) what are the observational constraints on such a primordial magnetic field?
The interdisciplinary project divides into the following related parts: (1) determining intergalactic magnetic field limits from currently available data; (2) studying cosmological large-scale correlated magnetic field generation mechanisms; (3) numerically studying the evolution of the magnetic field during the expansion of the universe; (4) numerically studying seed magnetic field amplification and dynamics during galaxy formation; and (5) predicting observable signatures of a cosmological seed magnetic field. This unique team of experts will significantly improve the current understanding of the origin, evolution, observational limits, and predicted signatures, of a cosmic magnetic field. The research includes important work in high energy physics, data analysis and interpretation, numerical simulation of magnetohydrodynamic processes, and galaxy and early structure formation. Perhaps most importantly, there is a chance to establish that observations demand a cosmological magnetic field that cannot be generated by any mechanism operating within the confines of the Standard Model of particle physics.
The educational aspects include the training of undergraduate and graduate students. A vigorous education and public outreach program involves the North Central Kansas Astronomical Society, the KSU Center for the Understanding of Origins, Theodore Roosevelt Elementary School (Manhattan, Kansas), Allegheny Observatory at the University of Pittsburgh, the Stanford University 'Splash!' events for high school students, and Pittsburg State University outreach events. And, as part of an international collaboration, the primary PI will conduct cosmology education sessions for undergraduate students at Abastumani Astrophysical Observatory, Georgia.
