Comparison of SPMI power as a function of planetary magnetic field strength at two orbital radii. Panel a shows the results for R_orb = 3.9, R_⋆, and panel b for R_orb = 5.9, R_⋆. The scatter points indicate simulation results; the solid lines represent power-law fits. The blue markers and lines denote S_r from simulations, the red squares and lines show the predictions from the Saur model, and the green hexagons and lines correspond to the Lanza model.