Production of zero energy radioactive beams through extraction across superfluid helium surface

Research output: Contribution to journalArticle


  • N. Takahashi
  • W. X. Huang
  • K. Gloos
  • P. Dendooven
  • J.P. Pekola

  • J. Äystö

Research units

  • University of Jyväskylä
  • Osaka Gakuin University
  • Niels Bohr Institute
  • University of Groningen
  • CERN


A radioactive 223Ra source was immersed in superfluid helium at 1.2-1.7 K. Electric fields transported recoiled 219Rn ions in the form of snowballs to the surface and further extracted them across the surface. The ions were focussed onto an aluminium foil and alpha particle spectra were taken with a surface barrier spectrometer. This enabled us to determine the efficiency for each process unambiguously. The pulsed second sound wave proved effective in enhancing the extraction of positive ions from the surface. Thus we offer a novel method for study of impurities in superfluid helium and propose this method for production of zero energy nuclear beams for use at radioactive ion beam facilities.


Original languageEnglish
Pages (from-to)1596-1597
Number of pages2
JournalPhysica B: Condensed Matter
Issue numberPart 2
Publication statusPublished - May 2003
MoE publication typeA1 Journal article-refereed

    Research areas

  • Impurities in superfluid helium, Radioactive ion beams, Radioactive snowballs, Second sound wave

ID: 4439558