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Star Formation and the Hall Effect

Mark Wardle
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Abstract

The breakdown of flux-freezing in molecular clouds and protostellar discs is usually approximated by ambipolar diffusion at low densities or by resistive diffusion at high densities. Here I discuss an intermediate regime in which the Hall term in the conductivity tensor is significant, and the vector evolution of the magnetic field -- and therefore the evolution of the system under consideration -- is dramatically altered. Calculations of charged particle abundances in dense gas in molecular clouds and protostellar discs demonstrate that Hall diffusion is important over a surprisingly broad range of conditions.

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Mark Wardle. 2003-07-04. Star Formation and the Hall Effect. https://doi.org/10.1023/b%3Aastr.0000045033.80068.1f

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