SHINE: Solar Wind Magnetic Field Discontinuities and the Role of Alfvenic Turbulence

SHINE：太阳风磁场不连续性和阿尔芬湍流的作用

• 批准号: 0850705
• 负责人: Bernard Vasquez
• 金额: $ 18.13万
• 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: 2009
• 资助国家: 美国
• 起止时间: 2009-03-01 至 2014-02-28
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0850705&HistoricalAwards=false
• 关键词: SHINE; Solar; Wind; Magnetic; Field

The Principal Investigator (PI) will investigate the relationship between magnetic field discontinuities and the dissipation of turbulence in the solar wind, using a new method to accurately identify even small discontinuities in the solar wind. In a small preliminary study, this new method found numerous discontinuities with thicknesses consistent with ion kinetic scales, and these could be locations that dissipate the turbulent cascade energy. The PI will extend this initial study to all Advanced Composition Explorer (ACE) spacecraft data from March 1998 to the present, covering an entire solar activity cycle. The PI will evaluate the statistical properties of any discontinuities that are found and compare them to properties of turbulent fluctuations at the inertial dissipation range spectral break. He will also compare discontinuity frequency and other properties with local estimates of the turbulent cascade rate. This effort will help describe how small scale structures arise and contribute to heating the solar wind, as well as constrain the mechanisms responsible for the dissipation of turbulent fluctuations and the heating of ions in the solar wind near 1 AU. The PI's work will address fundamental physical processes that determine the development and evolution of the solar wind in the inner heliosphere and how small-scale processes in the solar wind couple to large-scale dynamics. This project is important for modeling the energization of the ambient solar wind through which coronal mass ejections (CMEs) must travel.Dissipation of the turbulent cascade is believed to be an important source of energizing the solar wind near Earth, and potentially from the corona to the outer heliosphere. The PI therefore expects this research to provide new approaches for magnetohydrodynamics (MHD) solar wind simulations and to enhance the accuracy of space weather forecasting. This research program will include the training and participation of both undergraduate and graduate students at University of New Hampshire.

主要研究者（PI）将使用一种新方法来准确识别太阳风中的少量不连续性，从而研究磁场不连续性与湍流耗散之间的关系。在一项小型初步研究中，这种新方法发现了许多与离子动力学尺度一致的厚度的不连续性，并且这些位置可能是消散湍流级联能量的位置。 PI将将这项初步研究扩展到1998年3月的所有高级组成资源管理器（ACE）航天器数据，涵盖整个太阳活动周期。 PI将评估发现的任何不连续性的统计特性，并将其与惯性耗散范围频谱中断的湍流波动的特性进行比较。他还将将不连续频率和其他特性与湍流级联率的局部估计进行比较。这项工作将有助于描述小规模的结构如何出现并有助于加热太阳风，并限制导致湍流波动耗散的机制和在1 au附近太阳风中的离子加热。 PI的工作将解决基本的物理过程，这些过程决定了内层内太阳风的发展和演变，以及太阳风夫妇对大规模动力学的小规模过程如何。该项目对于建模环境太阳风的能量非常重要外气球。因此，PI希望这项研究为磁性水力学（MHD）太阳风模拟提供了新的方法，并提高了太空天气预测的准确性。该研究计划将包括新罕布什尔大学大学和研究生的培训和参与。