Interaction between the Electron-Cyclotron Emissions at(n+12)Ωeand the Ring-Current Protons in Space

The interaction between the electron-cyclotron emissions at $(n+\frac{1}{2}){\Omega }_e$ and the ring-curent protons is studied by using the linear-response theory of a turbulent plasma. The effective turbulent collisions come from the decay interactions between the electron-cyclotron turbulence and electrostatic ion-cyclotron waves. The ion-cyclotron waves generated by the generalized parametric resonance are effective for the loss of the ring-current protons. The critical electron-cyclotron-turbulence amplitude is consistent with the observed value.