Positron annihilation analysis

{
  "id": "MLC-T-CHM-009296",
  "term": "Positron annihilation analysis",
  "field": "Chemistry",
  "definition": "A non-destructive analytical technique that probes the electronic structure and defect properties of materials by detecting gamma rays produced during positron-electron annihilation. Positrons injected into a material thermalize and then annihilate with electrons, emitting two 511 keV gamma photons in opposite directions. This method is particularly sensitive to open-volume defects such as vacancies and voids in solids.",
  "synonyms": [
    "positron annihilation spectroscopy for chemical analysis (PASCA)"
  ],
  "subject": "Analytical Chemistry",
  "see_also": [
    "positron lifetime spectrometry"
  ],
  "references": [
    "PAC, 2021, 93, 69. 'Vocabulary of radioanalytical methods (IUPAC Recommendations 2020)' on page 92 (https://doi.org/10.1515/pac-2019-0302)"
  ],
  "url": "https://mlchart.com/terminology/chemistry/positron-annihilation-analysis/"
}