pub fn dc_emission_coefficient(x: f64, theta_z: f64) -> f64Expand description
DC emission coefficient K_DC(x, θ_z, θ_e).
K_DC = (4α/3π) θ_z² g_dc(x, θ_z, θ_e)
The emission/absorption term in the photon equation is: dn/dτ|_DC = (K_DC / x³) [n_eq - n]
where n_eq is the equilibrium distribution (Planck at the electron temperature).