Model Development and Theory/Data Closure for the Photoelectron-Driven Polar Wind

这项建议将进一步发展一个混合流体/动力学模型，并利用该模型研究极地风。 在这个模型中，热电子功能的极风流体计算描述，而超热电子功能，以及H+和O+离子描述使用动力学模型在全球环境中。 考虑了物种间的哥伦布碰撞，并自洽地计算了双极电场。 这种方法是第一个能够将光电子的全局碰撞物理纳入自洽描述的方法。 在探索性计算中产生了从亚音速碰撞状态到超音速无碰撞状态连续变化的全球稳态极风解。 这里的调查将首先致力于参数研究，以更好地了解各种电离层边界条件之间的复杂的相互关系及其对极风外流的影响。 模型研究的结果将与DE和Akebono卫星实验获得的极地风数据结果进行比较。

This proposal will further develop a hybrid fluid/kinetic model and use the model to investigate the polar wind. In this model, thermal electron features of the polar wind are described by fluid calculations while the suprathermal electron features, as well as H+ and O+ ions are described using a kinetic model in a global environment. Columbo collisions among species are taken into account and the ambipolar electric field is computed self consistently. This approach is the first to be able to incorporate the global collisional physics of photoelectrons into a self- consistent description. Global steady-state polar wind solutions that vary continuously from a subsonic collisional regime to a supersonic collisionless regime have been generated in exploratory calculations. The investigation here will be first devoted to parametric studies in order to better understand the complex inter- relations between various ionospheric boundary conditions and their effects on polar wind outflow. Results of the model investigations will be compared with results being obtained from polar wind data obtained from experiments on the DE and Akebono satellites.