五矩二流太阳风等离子体特性的数值研究

NUMERICAL STUDY ON PROPERTIES OF TWO-FLUID FIVE-MOMENT SOLAR WIND PLASMAS

本文数值求解了各向同性二流太阳风的五矩方程组,得出了1 R_s—2AU区域内太阳风密度、速度、电子和质子温度、它们的热流通量密度q以及非麦克斯韦分布尾部粒子过剩量ξ随日心距离的变化关系.文中比较了二流太阳风五矩模型、四矩模型(ξ=0)和低阶矩模型(不包括q和ξ二个矩方程)的等离子体特性,着重讨论了量ξ对质子温度及其热流通量的影响.结果表明,包括言的五矩方程可改善T_e/T_p和q_e/q_p的计算值与观测值的符合程度.

The variation with radial distance of partl;le density streaming velocity, temperature (T), heat flux (q) and excess (ζ) of non-Maxwellian tail particles in the electron and proton steady solar wind is numerically investigated by using spherically symmetric time-dependent five-moment fluid equations. The effects ofζ on the temperature and heat flux of protons are given special attention. The comparison of those plasma properties of the two-fluid solar wind between five-moment and four-moment models indicates that the moment equation of ζ can reduce the gap between observations and computations of Te/TP and qe/qp.