Intermittency and Ion Heating in Reduced Magnetohydrodynamic Turbulence

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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.