Amy Wendt edited untitled.tex  over 8 years ago

Commit id: 61ef97803ea092a5c34ae84ca170d40bb79db532

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Low pressure plasmas generated in pure oxygen have technological significance in a number of materials processing applications. Such processes rely on the interaction of neutral radicals, O$^+$ and O$_2^+$ with substrate surfaces exposed to the plasma. In many applications, achievement of process goals is sensitive to the relative fluxes of the different gas phase species to the substrate surface. Production of ion and neutral radical species occurs primarily through gas phase reactions involving collisions with energetic electrons, so that production {\it rates} are sensitive functions of electron density and electron temperature.  We propose an new outreach activity to increase public awareness of plasmas and their application, in partnership with the Rocket Club at Madison West High School. School (letter of collaboration included as ``supplementary documentation.''  Our group will work with Rocket Club members to create a hands-on display with a demonstration and description of ion thrusters for spacecraft propulsion, to be integrated into the club's existing outreach exhibit. As club participants, West High students engage in rocket competitions, local public outreach events and fund raising to support the club's activities. The club, founded in 2003, regularly participates in national competitions, including the Team America Rocket Challenge and the NASA Student Launch program, and has won numerous awards. Student members interact with the public through their exhibit at annual public outreach events, including the Wisconsin Science Festival and the University of Wisconsin Physics Fair, as well as visits to schools and other groups. The multifaceted exhibit includes rockets and payloads designed and built by the club as well as a ``build your own'' activity; designing and launching pneumatic paper rockets is a popular activity among visitors all ages. The new display will add a working plasma thruster to the exhibit, one that operates at atmospheric pressure and has a modest tabletop footprint, adapted from a recently published design\cite{make2015}. Operating at 300 watts, the thrust produced will be small, but observable through the deflection of a lightweight object such as a piece of paper in the path of the thruster ``exhaust.'' Visitors will also get a taste of plasma spectroscopy by looking at the thruster plasma through a low-cost diffraction gratings; distinct spectral features are expected in the visible portion of the spectrum. Additional diagnostics will include thermal sensors, which we expect to show a comparatively cool exhaust. The diagnostics may be utilized to spark discussions about efficiencies in converting energy sources to thrust; a very important consideration for long distance space travel.