JpGU-AGU Joint Meeting 2017

Presentation information

[EJ] Poster

P (Space and Planetary Sciences) » P-CG Complex & General

[P-CG24] [EJ] Planetary Magnetosphere, Ionosphere, and Atmosphere

Sun. May 21, 2017 1:45 PM - 3:15 PM Poster Hall (International Exhibition Hall HALL7)

convener:Kanako Seki(Graduate School of Science, University of Tokyo), Yoshiyuki O. Takahashi(Graduate School of Science, Kobe University), Hiromu Nakagawa(Planetary Atmosphere Physics Laboratory, Department of Geophysics, Graduate School of Science, Tohoku University), Keiichiro Fukazawa(Academic Center for Computing and Media Studies, Kyoto University)

[PCG24-P04] Pitch angle scattering due to elastic collisions between magnetospheric keV electrons and neutral H2O molecules originated from Enceladus

*Hiroyasu Tadokoro1, Yuto Katoh2 (1.Musashino University, 2.Tohoku University)

Keywords:Saturn, Enceladus, Pitch angle scattering

The observations of injected plasmas in the inner magnetosphere suggest that these particles do not survive very long time due to the neutral cloud originated from Enceladus [e.g., Paranicas et al., 2007; 2008]. These neutrals in the inner magnetosphere play the dominant role in a loss process of energetic electrons and ions [e.g., Paranicas et al., 2007; Sittler et al., 2008]. However, little has been reported on a quantitative study of the electron loss process due to electron-neutral collisions. In this study, we focus on the elastic collisional loss process with neutrals. Conducting one dimensional test-particle simulation, Tadokoro et al. [2014] examined the time variations of equatorial pitch angle distribution and electrons within loss cone through 1 keV electron pitch angle scattering due to electron-H2O elastic collisions around Enceladus when the electron flux tube passes the region of the dense H2O molecules in the vicinity of Enceladus (~380 sec). The result showed that the electrons of 11.4 % are lost in ~380 sec. Next remaining issue is loss rate of electrons with other energy. In this study, we show a preliminary result of the loss rate of electrons with 500eV-50keV. We also show the comparison of the loss rate between the high H2O density region (in the vicinity of Enceladus) and the low H2O density region (in the Enceladus torus).