Single escape peak

{
  "id": "MLC-T-CHM-010889",
  "term": "Single escape peak",
  "field": "Chemistry",
  "definition": "A peak observed in a gamma-ray spectrum that results from the escape of one of the two 0.511 MeV annihilation photons from the detector after a pair production event. When a high-energy photon interacts with the detector material and undergoes pair production, two annihilation photons are produced. If one escapes, the detected energy will be 0.511 MeV less than the full energy peak.",
  "subject": "Analytical Chemistry",
  "see_also": [
    "annihilation",
    "pair production",
    "photon"
  ],
  "references": [
    "PAC, 1982, 54, 1533. 'Glossary of terms used in nuclear analytical chemistry (Provisional)' on page 1541 (https://doi.org/10.1351/pac198254081533)"
  ],
  "url": "https://mlchart.com/terminology/chemistry/single-escape-peak/"
}