Stabilizers/antioxidants

Abstract

Observations on the satellite Geos 1 have shown the presence of banded emissions whose frequency spacing is of the order of the local He+ cyclotron frequency. Above the proton cyclotron frequency, the emissions are electrostatic in character whereas below they are electromagnetic. It is believed that these form the first observations of electrostatic ion cyclotron harmonic waves detected in the Earth's magnetosphere beyond ∼1RE. An investigation of the cold ion population at the times of the observed events indicates that helium ions from a large percentage of the total concentration, and occasionally may entirely dominate the population. Energetic ion distribution functions appear to peak in the energy range ≤ 30 keV, and show anisotropic pitch-angle distributions. Preliminary instability calculations using these observations are beginning to yield an insight into a mechanism whereby the waves can be produced.