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Expansion of Solid Helium into Vacuum: the Geyser Effect

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 Publication date 2004
  fields Physics
and research's language is English




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The particle flux through a two micron diameter orifice into vacuum from a source chamber filled with solid He exhibits a striking periodic behavior similar to that of a geyser. This phenomenon is attributed to a periodic collapse of the solid inside the source induced by the accumulation of excess vacancies injected at the orifice. The flux-time curves agree well with a kinetic model and provide direct information on the diffusivity of vacancies in solid He.



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