Derived Parameter: Electron Collision Frequency

Electron Collision Frequency

The electron-electron collision frequency given here is for the thermal case where two Maxwellians at nearly equal temperatures interact.

$\nu_{ee}= 3.0 \frac{n_e \ln \Lambda }{T^{3/2}} \ \ \mathrm{Hz}$

where n_e is electron density in cm^-3, T is in Kelvins, and

$\lambda_{ee} = \ln \Lambda=23.5 - \ln \left (1.2046 \times 10^5 \frac{\sqrt{n_e} }{T^{1.25}} \right ) - \sqrt{10^{-5} + \frac{\left ( \ln(T) - 11.35926 \right )^2}{16}$

Electron collision frequency values for quiet Sun (Model 1001; blue), facula (1005; red), and umbra (1006; green).

Model 1001 Electron Collision Frequencies (quiet Sun region)

Model 1005 Electron Collision Frequencies (strong facular region)

Model 1006 Electron Collision Frequencies (sunspot umbra)

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