Amplification of whistler‐mode hiss inside the plasmasphere

Chorus generated outside the plasmasphere has been suggested to be the source of plasmaspheric hiss. A detailed evaluation of the propagation and Landau damping of chorus waves can account for most of the properties of dayside hiss, but the intensity is underestimated by 10–20 dB compared to the observed hiss intensity. We show that this important discrepancy is due to the neglect of cyclotron resonant growth inside the plasmasphere. Careful modeling of the access of chorus to form an embryonic source outside the plasmapause, together with internal amplification inside the plasmasphere can account for the spectral intensity of dayside plasmaspheric hiss.