국내 최대 기계 및 로봇 연구정보

기술보고서

기술보고서 게시판 내용
타이틀	Background and Pickup Ion Velocity Distribution Dynamics in Titan''s Plasma Environment: 3D Hybrid Simulation and Comparison with CAPS T9 Observations
저자	Lipatov, A. S.;; Sittler, E. C., Jr.;; Hartle, R. E.;; Cooper, J. F.;; Simpson, D. G.
Keyword	ASYMMETRY;; BOUNDARY CONDITIONS;; CASSINI MISSION;; ELECTRON IMPACT;; HYDROGEN IONS;; ION DENSITY (CONCENTRATION); MAGNETOHYDRODYNAMIC FLOW;; MATHEMATICAL MODELS;; METHANE;; PLANETARY ENVIRONMENTS;; PLASMA INTERACTIONS;; SIMULATION;; THREE DIMENSIONAL FLOW;; TITAN;; VELOCITY DISTRIBUTION
URL	http://dx.doi.org/10.1016/j.asr.2011.05.026
보고서번호	GSFC.JA.5175.2011
발행년도	2011
출처	NTRS (NASA Technical Report Server)
ABSTRACT	In this report we discuss the ion velocity distribution dynamics from the 3D hybrid simulation. In our model the background, pickup, and ionospheric ions are considered as a particles, whereas the electrons are described as a fluid. Inhomogeneous photoionization, electron-impact ionization and charge exchange are included in our model. We also take into account the collisions between the ions and neutrals. The current simulation shows that mass loading by pickup ions H(+); H2(+), CH4(+) and N2(+) is stronger than in the previous simulations when O+ ions are introduced into the background plasma. In our hybrid simulations we use Chamberlain profiles for the atmospheric components. We also include a simple ionosphere model with average mass M = 28 amu ions that were generated inside the ionosphere. The moon is considered as a weakly conducting body. Special attention will be paid to comparing the simulated pickup ion velocity distribution with CAPS T9 observations. Our simulation shows an asymmetry of the ion density distribution and the magnetic field, including the formation of the Alfve n wing-like structures. The simulation also shows that the ring-like velocity distribution for pickup ions relaxes to a Maxwellian core and a shell-like halo.