Experimental Investigation of Ion Response to Propagating Alfvén Waves

离子对传播阿尔文波响应的实验研究

• 批准号: 0611571
• 负责人: EARL SCIME
• 金额: --
• 依托单位: West Virginia University Research Corporation
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-08-01 至 2009-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0611571&HistoricalAwards=false
• 关键词: Experimental; Investigation; Ion; Response; Propagating

The proposed project concerns a laboratory investigation of ion heating in the acceleration region of the fast solar wind. A number of mechanisms for ion heating in the fast solar wind have been proposed and this project will examine the possibility that the ions are directly heated by ion-cyclotron damping of Alfvn waves or that counter-propagating, low-frequency, Alfvn waves generate a turbulent cascade that heats ions by exciting higher frequency waves that then damp on the ions. The experiments will be performed in a space-relevant, laboratory plasma with sufficient diagnostic capability to investigate the evolution of the ion velocity space distribution function of majority and minority ions as they interact with propagating Alfvn waves, to observe Alfvn waves as they approach and possibly reflect from a strong gradient in the Alfven speed, and detect the generation of a nonlinear cascade if created by the counter-propagating waves. The effects of transverse flow on Alfven wave propagation will also be investigated and hybrid code modeling of the plasma will be performed in parallel with the experiments.The essential intellectual merit of the proposed activity is the performance of controlled laboratory experiments on phenomena that may play a key role in the acceleration and heating of the fast solar wind. Although Alfven wave propagation has been investigated by a number of different laboratory plasma research teams, the effects of plasma inhomogeneities, such as an Alfven speed gradient, and plasma flow have only recently been the subject of experimental attention. By choosing plasma conditions for which theory predicts a clearly defined outcome, the proposed experiments will provide a strong test of the theories now being applied to the acceleration region of the fast solar wind.

拟议的项目涉及对快速太阳风加速区域中离子加热的实验室研究。已经提出了许多在快速太阳风中加热离子加热的机制，该项目将检查离子通过离子 - 周期性阻尼Alfvn波的直接加热，或者是Alfvn波的导致离子加热的，或者是由Alfvn波的离子 - 循环阻尼，或者是通过激发较高的频率波动的湍流级联导致的湍流级联，然后将其反向传播，alfvn造成的，然后使较高的频率波动加热。实验将在与空间相关的实验室血浆中进行，具有足够的诊断能力，以调查多数和少数离子的离子速度速度空间空间分布功能的演变，因为它们与繁殖的AlfVn波相互作用，以观察Alfvn波，并可能在其接近时会逐渐反映出ALFVN，并在不合格的速度中构建了不合格的速度，并且如果Alfven的速度越来越多，并且构成了一个生成一代，并且可以构成一代人，并且可以构成一代人的一代。波浪。还将研究横向流对Alfven波传播的影响，并将与实验并行进行等离子体的混合代码建模。所提出的活动的基本知识优点是对现象的受控实验室实验的表现，该现象可能在加速和加热快速太阳能风中起关键作用。尽管许多不同的实验室等离子体研究团队已经研究了Alfven波传播，但血浆不均匀性的影响（例如Alfven速度梯度和血浆流量）直到最近才成为实验性关注的主题。通过选择理论预测明确定义结果的血浆条件，提出的实验将对现在应用于快速太阳风的加速区域的理论进行强有力的检验。