Earth Planets Space, Vol. 63 (No. 6), pp. 477-486, 2011
Tomoko Nakagawa1 and Shinya Kimura2
1Tohoku Institute of Technology, 35-1 Yagiyama Kasumi-cho, Taihaku-ku, Sendai, Miyagi 982-8577, Japan
2NTT Software Corporation, Teisan Kannai Bldg. 4F, 209, Yamasitatyo, Nakaku, Yokohama, Kanagawa 231-8551, Japan
(Received September 13, 2010; Revised January 31, 2011; Accepted February 9, 2011; Online published September 7, 2011)
The solar wind interaction with a non-magnetized, electrically non-conducting body is studied using a two-dimensional electromagnetic full particle simulation. The solar wind magnetic field is introduced into the simulation scheme as an initial condition together with the electric field generated by the motion of the solar wind. The solar wind magnetic field controls the direction of the thermal flow of the electrons and causes an asymmetry of the negative charging of the downstream-side surface. The negative charging and the potential drop are largest at the position where the solar wind magnetic field is perpendicular to the surface of the non-magnetized body. In the absence of photoelectrons, the solar wind electrons begin to be expelled by the negative charging at the terminator and then flow away along the field line producing streaks of enhancements of the electron density.
Key words: Wake, surface charging, electric potential, solar wind magnetic field, non-magnetized, electrically non-conducting body, 2D electromagnetic PIC simulation.