Magnetic diffusivity

The magnetic diffusivity is a parameter in plasma physics. It appears in the Magnetic Reynolds number. The magnetic diffusivity is defined as^[1]:

$\eta = \frac{1}{\mu_0 \sigma_0}$ .

$μ 0$ is the permeability of free space.
is the plasma conductivity due to Coulomb or neutral collisions.
- $n e$ is the electron density.
- $e$ is the electron charge.
- $m e$ is the electron mass.
- $ν c$ is the collision frequency.

References

^ W. Baumjohann and R. A. Treumann, Basic Space Plasma Physics, Imperial College Press, 1997

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Plasma physics

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