Intermittency and Ion Heating in Reduced Magnetohydrodynamic Turbulence

减少磁流体动力湍流中的间歇和离子加热

• 批准号: 1500041
• 负责人: Benjamin Chandran
• 金额: $ 28万
• 依托单位: University of New Hampshire
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-06-01 至 2019-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1500041&HistoricalAwards=false
• 关键词: Intermittency; Ion; Heating; Reduced; Magnetohydrodynamic

This project will advance the scientific community's understanding of turbulence in the solar wind, which is the quasi-steady outflow of high-temperature, ionized gas (plasma) from the Sun. Turbulence plays a key role in heating and accelerating the solar wind, which in turn mediates the interactions between the Sun and Earth's near-space environment. This project will thus ultimately contribute to the scientific community's ability to understand and model space weather, which includes disturbances in the Earth's magnetic field that have the potential to damage power grids. In addition, this project will contribute to the training of future scientists by supporting the research team's involvement in, and organization of, the annual Solar Heliospheric and INterplanetary Environment (SHINE) Workshop. This Workshop attracts roughly 200 attendees, of whom approximately 60 are students. The Workshop provides students with specialized training in space science and helps integrate students into the community of space-science researchers. The principal investigator of the project will teach in summer schools for undergraduate students, graduate students, and postdoctoral researchers in the fields of plasma physics and space physics. The principal investigator will also incorporate research findings from this project into his teaching of physics and astronomy at the University of New Hampshire. These activities will contribute to the development of a strong science-technology-engineering-mathematics (STEM) workforce, which will benefit society at large.The particular scientific focus of the project's turbulence research is on the phenomenon of intermittency and its effects upon solar-wind turbulence. Intermittency is a property of turbulent flows in which random fluctuations in, for example, the velocity of the medium (``eddies'') become concentrated into a decreasing fraction of the volume as the size of the eddies decreases. Intermittency profoundly impacts almost every aspect of solar-wind turbulence, from the rate at which it heats the interplanetary medium to the mechanisms by which turbulent energy is transferred to the different types of charged particles contained in the solar wind. To tackle this problem, the research team will employ a range of methodologies, including mathematical modeling and computer simulations, and they will test their theoretical predictions using spacecraft measurements.

该项目将促进科学界对太阳风中的湍流的理解，这是来自太阳的高温，电离气体（等离子体）的准稳态流出。湍流在加热和加速太阳风中起着关键作用，这反过来介导了太阳和地球近空间环境之间的相互作用。因此，该项目最终将有助于科学界理解和建模太空天气的能力，其中包括地球磁场中有可能损害电网的干扰。此外，该项目将通过支持研究团队参与和组织年度太阳能地球际和行星际环境（Shine）研讨会来为未来科学家的培训做出贡献。这个研讨会吸引了大约200名与会者，其中约60名学生。该研讨会为学生提供了太空科学方面的专门培训，并帮助将学生纳入空间科学研究人员社区。该项目的主要研究人员将在暑期学校为大学生，研究生和血浆物理学领域的博士后研究人员教授。首席研究人员还将将该项目的研究结果纳入他在新罕布什尔大学的物理和天文学教学中。这些活动将有助于开发强大的科学技术工程学数学（STEM）劳动力，该劳动力将使社会上的整个社会受益。该项目的湍流研究的特殊科学重点是与太阳能湍流的影响及其对太阳能湍流的影响。 间歇性是湍流的特性，其中，随着介质的速度（``'eddies''）的随机波动集中在体积的减少分数中，而随着涡流的尺寸降低。间歇性深刻地影响了太阳风湍流的几乎每个方面，从加热行星际介质到将湍流能量转移到太阳风中包含的不同类型的带电颗粒的机制。为了解决这个问题，研究团队将采用一系列方法，包括数学建模和计算机模拟，他们将使用航天器测量值测试其理论预测。