Studies of Wave-Particle Interactions for Interstellar Pickup Ions in the Solar Wind

太阳风中星际拾取离子的波粒相互作用研究

• 批准号: 0635863
• 负责人: Philip Isenberg
• 金额: $ 32.6万
• 依托单位: University of New Hampshire
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2007
• 资助国家: 美国
• 起止时间: 2007-01-01 至 2011-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0635863&HistoricalAwards=false
• 关键词: Studies; Wave; Particle; Interactions; Interstellar

The proposer has recently modeled the scattering of interstellar pickup protons, including wave dispersion and multiple resonances, under conditions appropriate to the distant equatorial heliosphere. The wave power generated by this scattering was used to drive a turbulent cascade which heated solar wind protons through its dissipation. Although the model reproduced much of the particle temperature behavior observed by Voyager 2, the results at the greatest radial distances showed too much heating, indicating that model improvements were needed. The PI now plans several new studies of these wave-particle interactions (which influence the evolution of turbulence, dominate energy fluctuations in the outer heliosphere, and determine the effect of interstellar pickup ions on the solar wind environment), while improving the model's treatment of turbulence. The PI will incorporate thermal effects into the dispersion of resonant waves in his equatorial model. He will then extend the model's treatment of dispersive resonant scattering to include the unequal intensities of inward and outward propagating waves produced by pickup in a non-azimuthal magnetic field. This more general analysis will allow the modeling of turbulent evolution at all heliolatitudes. The PI will also apply this new dispersive analysis to the behavior of pickup ions in a quasi-radial magnetic field, in order to address questions concerning sporadic wave generation and incomplete pitch-angle scattering associated with in situ pickup ion observations.

在适合远处赤道赤道地球层的条件下，提议者最近对星际拾音器质子的散射（包括波散和多个共振）进行了建模。该散射产生的波动功率用于驱动湍流的级联反应，该级联反质质子通过其耗散加热。尽管该模型再现了Voyager 2观察到的许多颗粒温度行为，但最大的径向距离的结果显示出太多的加热，表明需要改进模型。 PI现在计划了几项有关这些波粒子相互作用的新研究（这会影响湍流的演变，主导地球外的能量波动，并确定星际拾音器离子对太阳风环境的影响），同时改善了模型的湍流处理。 PI将在其赤道模型中将热效应纳入共振波的分散体中。然后，他将扩展模型对色散谐振散射的处理，以包括拾音器在非齐路磁场中产生的内向和向外传播波的不等强度。这种更一般的分析将使湍流演化在所有的热拟人座上进行建模。 PI还将将这种新的分散分析应用于准辐射磁场中的拾音器行为，以解决有关零星波的产生和与原位拾取离子观测相关的不完整的俯仰角散射的问题。