Highly Charged Droplets of Superfluid Helium.

@article{Laimer2019HighlyCD,
  title={Highly Charged Droplets of Superfluid Helium.},
  author={Felix Laimer and Lorenz Kranabetter and Lukas Tiefenthaler and Simon Albertini and Fabio Zappa and Andrew M. Ellis and Michael Gatchell and Paul Scheier},
  journal={Physical review letters},
  year={2019},
  volume={123 16},
  pages={
          165301
        }
}
We report on the production and study of stable, highly charged droplets of superfluid helium. Using a novel experimental setup we produce neutral beams of liquid helium nanodroplets containing millions of atoms or more that can be ionized by electron impact, mass-per-charge selected, and ionized a second time before being analyzed. Droplets containing up to 55 net positive charges are identified and the appearance sizes of multiply charge droplets are determined as a function of the charge… 

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