Abstract
Abstract. Pitch-angle diffusion coefficients have been calculated for resonant interaction with electrostatic electron cyclotron harmonic (ECH) waves in the magnetospheres of Earth, Jupiter, Saturn, Uranus and Neptune. Calculations have been performed at two radial distances of each planet. It is found that observed wave electric field amplitudes in the magnetospheres of Earth and Jupiter are sufficient to put electrons on strong diffusion in the energy range of less than 100 eV. However, for Saturn, Uranus and Neptune, the observed ECH wave amplitude are insufficient to put electrons on strong diffusion at any radial distance.
Highlights
Electrostatic electron cyclotron harmonic (ECH) waves are virtually ubiquitous in planetary magnetospheres
We extend the calculations of pitch-angle diffusion coefficients for resonant interaction with ECH waves in the magnetospheres of Earth, Jupiter, Saturn, Uranus and Neptune
The ECH waves of natural origin were first observed by the OGO-5 satellite (Kennel et al, 1970; Fredricks and Scarf, 1973) as narrow band ( f/fc ≈ 1.0), large amplitude (1–10 mV m−1) waves that appear within a frequency range of 1.25fc < f < 1.75fc
Summary
Horne and Thorne (2000) have calculated the bounceaveraged pitch-angle diffusion rates for electrostatic ECH waves driven by a loss-cone distribution They have concluded that ECH waves can scatter keV electrons into the loss-cone efficiently and can contribute directly to the loss to the atmosphere. We extend the calculations of pitch-angle diffusion coefficients for resonant interaction with ECH waves in the magnetospheres of Earth, Jupiter, Saturn, Uranus and Neptune. This will provide a comparative study of pitch-angle diffusion in producing diffuse aurora in planetary atmospheres for the first time. The comparison of pitch-angle diffusion with strong diffusion and precipitation of energetic electrons into the atmosphere of each planet and results and discussion of this study, are presented in Sect.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
