Fig. 3
From: Determining polar ionospheric electrojet currents from Swarm satellite constellation magnetic data
Normalized L-curves for 6 individual orbits: orbit no. 200 with Kp index of \(1^-\) (orange), orbit no. 2000 with Kp index of \(1^+\) (yellow), orbit no. 3334 with Kp index of \(3^-\) (dark blue), orbit no. 6248 with Kp index of \(4^-\) (light green), orbit no. 6493 with Kp index of \(0^+\) (light blue), and orbit no. 8000 with Kp index of \(1^+\) (purple). Five different \(\alpha ^2\)s are highlighted to show how changes in complexity and model fit change with changing values of \(\alpha ^2\), \(\alpha _1^2=1.8\cdot 10^{-16}\frac{\text {nT}^2}{\text {A}}\), \(\alpha _2^2=5.4\cdot 10^{-16}\frac{\text {nT}^2}{\text {A}}\), \(\alpha _3^2=1.2\cdot 10^{-15}\frac{\text {nT}^2}{\text {A}}\), \(\alpha _4^2=6.3\cdot 10^{-15}\frac{\text {nT}^2}{\text {A}}\), and \(\alpha _5^2=6.0\cdot 10^{-14}\frac{\text {nT}^2}{\text {A}}\)