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Expansion of Solid Helium into Vacuum: the Geyser Effect

R. E. Grisenti·M. Kaesz·J. P. Toennies·G. Benedek·F. Dalfovo
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Abstract

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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R. E. Grisenti, M. Kaesz, J. P. Toennies, G. Benedek, F. Dalfovo. 2004-03-25. Expansion of Solid Helium into Vacuum: the Geyser Effect. https://arxiv.org/abs/cond-mat/0403642

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