Top: production rates of primary (dashed lines) and secondary (dotted lines) electrons from the MUS-a and -b models. Colors separate the contributions by donor. The dashed black line refers to the primaries summed over all donors. The solid black line refers to the total of primaries and secondaries summed over all donors. Bottom: number densities. Dashed and solid lines refer to MUS-a and -b, respectively. Each panel provides, based on the MUS-b model, the conversion between pressure and radial distance normalized to the planet’s optical radius (r/R_p; =1 at the model’s lower boundary).