6:15 PM - 7:30 PM
[PEM26-P10] Test-particle simulation of electron elastic collision with neutral H2O molecule originated from Enceladus
Keywords:Test particle simulation, elastic collision, Enceladus, Saturn
In the present study, we examine the variation of energetic electron pitch angle distribution at the magnetic equator and loss rate of precipitated electrons into Saturn's atmosphere through pitch angle scattering due to elastic collisions with neutral H2O along Saturn's dipole magnetic field line around Enceladus. We conduct one dimensional test-particle simulation for monoenergetic electrons along Saturn's dipole magnetic field line around Enceladus when the co-rotating electron flux tube passes the dense H2O region in the vicinity of Enceladus (~6.4 minutes). The initial electron pitch angle distribution is assumed to be isotropic. In case of 1 keV electron, Tadokoro et al.,  showed that
1.the equatorial electron pitch angle distribution near the loss cone (<20 degrees and >160 degrees) decreases with time through pitch angle scattering due to elastic collisions and that the distribution around 90 degrees shows significant scattering due to the dense region of H2O,
2. It is found that the electrons of ~19 % to the total number of equatorial electrons at the initial condition are lost in ~380 seconds.
3.The calculated loss time is fourth faster than the loss time under the strong diffusion.
We also show the loss rates through pitch angle scattering of electrons with not only 1 keV but also several hundreds eV ? several tens of keV.