University of Kansas Cassini Studies

DRAFT Ion Trajectories in Saturn's Magnetosphere Near Titan S. A. Ledvina, T. E. Cravens, A. Salman, and K. Kecskemety

The effects Titan has on various ion trajectories are listed below.

1. The trajectories of the ambient ions are unaffected by the presence of Titan unless they pass with the magnetic barrier located between 1-2 RT in the ram, flank or polar regions, or interact with Titan's wake structure. Outside this region the ion trajectories resemble the trajectories of ions in the unperturbed plasma flow with a uniform electric and magnetic field.
2. The gyroradii of pick-up ions are much smaller in the near-Titan region, due to the magnetic barrier, and in the wake structure than they are outside of this region.
3. Once pick-up ions leave the near-Titan region, their trajectories resemble the trajectories of ambient ions in the outer region and the trajectories of ions in an unperturbed plasma flow.

In this work we have taken a look at how the trajectories of N+ ions in Saturn's magnetosphere are affected by the presence of Titan. We have used the output from the three-dimensional model of Ledvina and Cravens (1998) to find the forces acting on the ion and solve the equation of motion (eq. 1). Future work will include a more realistic obstacle and higher spatial resolution MHD model. In addition, more work will be done on the statistics in order to further understand this plasma interaction and the roles of the ambient and pickup ions. This work illustrates the need for self-consistent hybrid simulations, to better understand this interaction, due to the large gyroradii of ions in Saturn's magnetosphere. Ultimately the Cassini mission is needed to collect data on the plasma interaction between Titan and Saturn's magnetosphere.

References

Return to Ion Trajectories Near Titan Main Abstract and Index Page.
Return to Space Physics Main Cassini Page.
Return to Titan Studies Main Page.

Last modified February 2, 2004 T. Hunt-Ward tizby@ku.edu