Excitation of Saturnian ECH Waves Within Remote Plasma Injections: Cassini Observations

Based on Cassini observations, we report representative electrostatic electron cyclotron harmonic (ECH) wave events observed in Saturn's magnetosphere within remote plasma injections. Unlike local injections, injections are “older” injection that have evolved to form a dispersed signature particle energy spectrum. We show Saturnian ECH waves present strong fundamental band and much weaker high bands. By calculating the linear growth rates based measured velocity distributions, indicate can be excited by loss cone distribution of remotely injected, hot electrons ∼100 eV several keV. find tend intensify with increased fluxes injected but weakening evolution time flux tubes, which is consistent results improves current understanding generation at Saturn.