MRI: Development of the PHAse Space MeAsurements (PHASMA) Experiment

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One of the challenges in understanding naturally occurring phenomena in outer space is how difficult it is to perform scientific measurements throughout the region of interest. Another challenge is that nature is rarely kind enough to produce the exact same event over and over again so that scientists can distinguish random fluctuations in their measurements from those that result from the phenomena of interest. The phenomena in space of particular interest are those that play important roles in the space environment around the Earth and which can impact human infrastructure in space, e.g., satellites, manned space vehicles, etc., and technological systems on Earth, e.g., power grids, global positioning systems (GPS), and long distance radio communication. This project involves the construction of a laboratory facility capable of producing plasma phenomena like those that occur in space. Plasmas are gasses so hot that the electrons are stripped away from their atoms. The resulting collection of charged particles responds to both electric and magnetic fields, just like plasmas in space. This particular facility will investigate how the ions and electrons in plasmas are heated and accelerated when magnetic fields annihilate, when the plasma is turbulent, or when the plasma moves faster than the speed of sound. The facility will engage a consortium of plasma physics researchers throughout West Virginia. The broader impacts of this work will also include the training of graduate and undergraduate students in a research environment that synergistically combines experimental and theoretical plasma physics and attracts high quality undergraduates into physics through involvement in cutting-edge research activities.While there is a strong synergy between laboratory experiments and other approaches to studying space physics, there are currently no space-relevant experiments in the world making direct measurements of three-dimensional ion and electron distribution functions in a plasma volume. The instrument to be developed under this award, called the PHAse Space MeAsurements (PHASMA) experiment, features laser induced fluorescence diagnostics for ion measurements, Thomson scattering diagnostics for electron velocity distribution function measurements, and a microwave scattering system for turbulence measurements. Spacecraft measurements have advanced to the point where velocity distribution function measurements are leading to paradigm-changing insights about a broad spectrum of space plasma phenomena. The ability to directly measure velocity distribution functions in the lab will complement and enhance the value of the direct measurements made in space. The PHASMA experiment will enable studies of particle acceleration and plasma heating in magnetic reconnection, collisionless shocks, and plasma turbulence. The experimental facility research team includes members with unique strengths in particle diagnostic measurements and expertise in kinetic modeling -- making the team ideally suited to investigate these topics.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.