Modeling Source Surface Plasma and Magnetic Field Based on Expansion Factor f(S) and Angular Distance theta(b) Between the Foot Points

The purpose of this paper is to model the distribution of plasma and magnetic field on the source surface of 2.5 R-S covering four different phases of solar activity. We use the expansion factor f(S) and the angular distance theta(b) in specifying the solar wind speed on the source surface, which can separate the open field region and the close field region effectively. We select 136 Carrington Rotations (CRs) covering four different phases of solar activity, and use an empirical model of the magnetic field topology by Wilcox Solar Observatory (WSO) and an empirically derived global coronal density distribution by MKIII in High Altitude Observatory (HAO) as input. The solar wind speed at 1AU derived from the new distribution on the source surface works much better than one derived from the previous method (Shen et al. 2010), as compared with observational data.