日冕扰动传播的数值模拟(Ⅲ)太阳风的影响

A NUMERICAL SIMULATION FOR THE PROPAGATION OF DISTURBANCE IN THE SOLAR CORONA (III) THE EFFECTS OF SOLAR WIND

本文数值研究了二维磁流体动力学平衡基态下开场区日面冷物质径向喷射所引起的日冕动力学响应。结果表明:(1)在高密度环前方有一弱扰动区近似以Alfvén速度向外传播;(2)高密度环前缘移动速度随着径向距离而增加,其增加值近似为局地太阳风速度;(3)高密度环中等离子体的最大径向速度约在4个太阳半径处趋于局地逃逸速度;(4)对于强开放场,环形结构在θ方向上没有明显的扩张。这些结果可以更好地解释伴随有日珥的日冕物质抛射事件。

In this paper, the dynamical response under the basic state with two-dimensional magne-tohydrodynamic equilibrium in the solar corona caused by the radial ejection of cold mass at the solar surface of the open magnetic field is studied numerically. The results show that: (1) a weak disturbance propagates upwards with the Alfven velocity on the front of loop with high plasma density; (2) the moving velocity of the leading edge of loop increases as the radial distance increases, and the increment is nearly equal to the local velocity of solar wind; (3) the maximum of plasma radial velocity in the loop approaches to the local escape velocity at four solar radii; (4) the feet of loophave not any obvious expansion for the open region with stroni magnetic field. These results may explain the solar prominence and the accompanying coronal mass ejection.