Plasma Parameter: Alfvén speed

Alfvén Speed

The Alfvén speed v_A is the speed of the Alfvén mode of magnetohydrodynamic waves.

$\nu_A =\frac{B}{\sqrt{4\pi n_{tot} m_H}} \approx 2.18 \times 10^{11} \frac{ B}{\sqrt{n_{tot}}}\ \ \mathrm{cm/s}$

where n_tot = n_p + n_H, neglecting the electron mass, and B is in gauss in the dimensional formula.

Alfvén speeds for Fontenla Model 1001 (blue; 30 G), Model 1005 (red; 300 G), and Model 1006 (green; 3000 G).

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