A new constraint on mean-field galactic dynamo theory

作者:Chamandy Luke; Singh Nishant K
来源:Monthly Notices of the Royal Astronomical Society, 2017, 468(3): 3657-3662.
DOI:10.1093/mnras/stx706

摘要

Appealing to an analytical result from mean-field theory, we show, using a generic galaxy model, that galactic dynamo action can be suppressed by small-scale magnetic fluctuations. This is caused by the magnetic analogue of the Radler or Omega x J effect, where rotation-induced corrections to the mean-field turbulent transport result in what we interpret to be an effective reduction of the standard a effect in the presence of small-scale magnetic fields.

  • 出版日期2017-7