Swift ion

{
  "id": "MLC-T-CHM-011714",
  "term": "Swift ion",
  "field": "Chemistry",
  "definition": "An ion moving faster than the Bohr speed, c/137, where c is the speed of light and the Bohr speed is that of the electron in the first Bohr orbit of hydrogen. Such an ion loses energy mainly by exciting and ionizing target electrons, through electronic stopping, rather than by collisions with nuclei. The criterion corresponds to about 25 keV per atomic mass unit, so it requires more than 1 MeV for argon and 5 MeV for gold.",
  "subject": "Analytical Chemistry",
  "references": [
    "PAC, 2020, 92, 1781. 'Glossary of methods and terms used in surface chemical analysis (IUPAC Recommendations 2020)' on page 1836 (https://doi.org/10.1515/pac-2019-0404)"
  ],
  "url": "https://mlchart.com/terminology/chemistry/swift-ion/"
}