Simulations of Galactic Dynamos
Number of Authors: 1
2015 (English)In: Magnetic Fields in Diffuse Media / [ed] Lazarian, A.; DalPino, E.M.D.; Melioli, C., Dordrecht: Springer, 2015, Vol. 407, 529-555 p.Chapter in book (Refereed)
We review our current understanding of galactic dynamo theory, paying particular attention to numerical simulations both of the mean-field equations and the original three-dimensional equations relevant to describing the magnetic field evolution for a turbulent flow. We emphasize the theoretical difficulties in explaining non-axisymmetric magnetic fields in galaxies and discuss the observational basis for such results in terms of rotationmeasure analysis. Next, we discuss nonlinear theory, the role of magnetic helicity conservation and magnetic helicity fluxes. This leads to the possibility that galactic magnetic fields may be bi-helical, with opposite signs of helicity and large and small length scales. We discuss their observational signatures and close by discussing the possibilities of explaining the origin of primordial magnetic fields.
Place, publisher, year, edition, pages
Dordrecht: Springer, 2015. Vol. 407, 529-555 p.
, Astrophysics and Space Science Library, ISSN 0067-0057 ; 407
IdentifiersURN: urn:nbn:se:su:diva-121082DOI: 10.1007/978-3-662-44625-6_19ISI: 000357594300020ISBN: 978-3-662-44625-6ISBN: 978-3-662-44624-9OAI: oai:DiVA.org:su-121082DiVA: diva2:856479