Ab Initio Simulations of a Supernova-driven Galactic Dynamo in an Isolated Disk Galaxy

  title={Ab Initio Simulations of a Supernova-driven Galactic Dynamo in an Isolated Disk Galaxy},
  author={Iryna S. Butsky and Jonathan Zrake and Ji-hoon Kim and Hung-I Yang and Tom Abel},
  journal={The Astrophysical Journal},
We study the magnetic field evolution of an isolated spiral galaxy, using isolated Milky Way–mass galaxy formation simulations and a novel prescription for magnetohydrodynamic (MHD) supernova feedback. Our main result is that a galactic dynamo can be seeded and driven by supernova explosions, resulting in magnetic fields whose strength and morphology are consistent with observations. In our model, supernovae supply thermal energy and a low-level magnetic field along with their ejecta. The… 

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