A Survey of Electron Beams Associated With Saturnian Auroral Hiss
A.J. Kopf, D.A. Gurnett, G.B. Hospodarsky, W.S. Kurth, J.D. Menietti, M.K.
Dougherty, D.G. Mitchell, J.S. Leisner, K.K. Khurana, S. Grimald, C. Arridge, P.
Schippers, N. Andre, A. Coates, O. Santolik
Over the last three years, the Cassini spacecraft underwent a series of high
inclination orbits, allowing investigation and measurements of the Saturnian
auroral zone. The Radio and Plasma Wave Science (RPWS) Investigation has
detected low frequency funnel-shaped whistler mode emissions along the auroral
field lines, much like the auroral hiss observed at Earth. The poleward and
equatorward flaring of the auroral hiss funnel on the frequency-time spectrogram
is the result of whistler mode waves propagating upward into a region of
diminishing plasma density. These detections are important in understanding the
auroral processes occurring at Saturn. Recent efforts have focused on
integrating RPWS data with that from other instruments, particularly from the
CAPS-ELS investigation. Electron beams are known to be the source of auroral
hiss emission at Earth, and it is generally believed the same is true at Saturn.
Current work has focused on correlating these beams with the observed radio
emission, along with modeling the beams to calculate their growth rates. One
electron beam has already been analyzed from the high-latitude pass on October
17, 2008. This beam was determined to be propagating upward from Saturn, and
has been found to produce a large whistler-mode growth rate, which fits with the
auroral hiss model. More electron beams will be analyzed in this fashion over
the coming months. These results will be the focus of this presentation.
Back to Conferences and Presentations
Back to Andrew's Home Page
