What is coincidence detection in PET? Coincidence detection is the method by which PET scanners identify and record pairs of gamma photons produced during positron annihilation. When two 511 keV photons are detected simultaneously (within a very short time window)…
What happens during positron annihilation? Positron annihilation occurs when a positron (the antimatter counterpart of an electron) encounters an electron. The two particles destroy each other, and their mass is converted into energy in the form of two gamma photons,…
What is isomeric transition? Isomeric transition is a type of radioactive decay in which an excited nucleus releases excess energy without changing its number of protons or neutrons. The nucleus remains the same element and isotope but moves from a…
What is electron capture? Electron capture is a type of radioactive decay in which a proton inside an unstable nucleus captures an inner-shell electron (usually from the K shell) and is converted into a neutron. As a result, the atomic…
What is beta plus (β⁺) decay? Beta plus (β⁺) decay, also known as positron emission, is a type of radioactive decay in which a proton inside an unstable nucleus is converted into a neutron, with the emission of a positron…
What is beta minus (β⁻) decay? Beta minus (β⁻) decay is a type of radioactive decay in which a neutron inside an unstable nucleus is converted into a proton, with the emission of an electron (the beta particle) and an…
What is radioactive decay? Radioactive decay is the spontaneous transformation of an unstable atomic nucleus into a more stable configuration, accompanied by the emission of radiation. This process occurs because the original nucleus has an imbalance of forces or an…
What is mass defect and how does it relate to E = mc2? Mass defect is the difference between the combined mass of a nucleus’s individual protons and neutrons and the actual measured mass of the bound nucleus. The bound…
What is binding energy per nucleon and why is it important? Binding energy per nucleon is the average amount of energy required to remove a single proton or neutron from a nucleus. It is calculated by dividing the total nuclear…
What is nuclear binding energy? Nuclear binding energy is the energy required to completely separate a nucleus into its individual protons and neutrons. It represents how strongly the nucleons are held together by the strong nuclear force. The greater the…