Nordita Astrophysics Seminars

Transition from turbulent scale to mean-field scale dynamo in a supernova-driven multiphase ISM

by Dr Frederick Gent (Aalto University & Nordita)

Albano 3: 6228 - Mega (22 seats) (Albano Building 3)

Albano 3: 6228 - Mega (22 seats)

Albano Building 3


Magnetic fields are ubiquitous throughout galaxies, affect our observations and are important to the dynamics of the ISM and galactic structure at multiple scales. The magnetic fields must be sustained by various dynamo processes, which action may complement or interfere with each other. The turbulent or small-scale dynamo (SSD) amplifies the magnetic field in galaxies relatively rapidly from a picoGauss to a few microGauss (~Myr), such that even very young galaxies likely have magnetic fields with sufficient energy to affect their dynamics. The mean-field dynamo driven by rotation and gravity on galactic scales evolve much more slowly over Gyr timescales. We shall present the results of high resolution simulations that have been integrated over tens of millions of cpu hours. These enable us to study the nature of these dynamo modes separately and interacting to better understand the growth rates and structure of the galactic dynamo.