Magnetic fields in star-forming galaxies at low and high redshifts
نویسنده
چکیده
Magnetic fields in nearby galaxies are amplified and structured by compressing and shearing gas flows and by dynamo action. Large-scale coherent fields can be expected in young galaxies after several 10yr, while turbulent flows and small-scale dynamos can generate turbulent magnetic fields on the timescale of the first supernova explosions. Frequent interactions and ram pressure in the early Universe produced strong anisotropic fields. Distant, unresolved galaxies are expected to be polarized in radio continuum and will be ideal sources for the SKA all-sky survey of Faraday rotation measures. Models of magnetic field evolution in galaxies are required to investigate the relation of total radio continuum emission to the star-formation rate.
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تاریخ انتشار 2008