Abstract
A theory is developed of vortex nucleation by an ion moving in superfluid helium at a low temperature. It is shown that production of a vortex loop attached to the side of the ion becomes energetically possible when the velocity of the ion exceeds a critical value, but that nucleation is impeded by the presence of a small potential barrier. The predicted critical velocity is close to that observed experimentally, at least at high pressure. Nucleation of an encircling vortex ring, considered some years ago by Schwarz & Jang (Phys.Rev. A8,3199 (1973)), probably becomes possible only at a higher velocity, and it is impeded by a large potential barrier. It is shown that for vortex loops the potential barrier can probably be overcome at a rate consistent with experiment either by quantum tunnelling at the lowest temperatures or thermally, by absorption of a single roton, at higher temperatures. Possible explanations of the recent observation by Bowley
et al
. {Phil. Trans. R. Soc. Lond. A307, 201 (1982)) that at high pressure the rate of vortex nucleation falls off at very high velocities are discussed.
Reference41 articles.
1. A Ilu m D . R . M c C lin to c k P. V . E . P h illip s A . & B o w ley R . M . 1977 P hil. Trans. R . Soc. Lond. A 2 8 4 1 7 9 -2 2 4 .
2. B lood F. A . 1976 Physics Fluids 19 1 4 3 5 -1 4 3 8 .
3. Phil. Trans. R. Soc. Lond. A 1982 3
4. Phys. Rev. Lett. 1980 4
5. Comparative study of uniaxial channeling-blocking and single-alignment channeling backscattering—reversibility and defect analysis
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