Ion cyclotron waves in the Jovian magnetosphere

Abstract

Magnetic field data from the inbound Ulysses flyby past Jupiter in February 1992 is examined for evidence of ion cyclotron wave activity. Particular interest has been paid to the near equatorial current sheet within the middle magnetosphere where the field magnitude ranges between 5-60 nT. Power spectral peaks in the ion cyclotron range are easily resolved in the high resolution one second data, with the peaks being related to ion cyclotron frequencies in the heavy ion gyrofrequencies regime. Linearly as well as right and left hand circularly polarised waves are observed and in general the power in the transverse components of the wave are an order of magnitude higher than those in the compressional wave.