作者: Dinshaw S. Balsara , Grant J. Mathews , Mordecai-Mark Mac Low , Jongsoo Kim
DOI: 10.1086/425297
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摘要: Several lines of evidence suggest that magnetic fields grow rapidly in protogalactic and galactic environments. However, mean field dynamo theory has always suggested the rather slowly, taking order a Hubble time to reach observed values. The theoretical difficulties only become worse when system high Reynolds number, as is case for discrepancy can be reconciled if fast processes amplifying could operate. Following 2001 work Balsara coworkers, we show an interstellar medium dominated by realistic energy input from supernova explosions will naturally strongly turbulent with large positive negative values kinetic helicity. Even though driven compressible motions, this Mach number flow mainly concentrated solenoidal than motions. These results stem interaction strong shocks each other turbulence they self-consistently generate our model. Moreover, also generates helicities either sign. model two characteristics dynamo: growth independent scale comparable eddy turnover time. This linear phase permits until reaches about 1% energy. At stage, astrophysical producing take over. Energetics, power spectra, statistics, structures are studied here. Shock-turbulence shown very general mechanism helicity generation amplification, applicability damped Ly? systems, protogalaxies, Galaxy, starburst galaxies, intracluster medium, molecular clouds.