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Positron emission is mediated by the weak force. The positron is a type of beta particle (β +), the other beta particle being the electron (β −) emitted from the β − decay of a nucleus. An example of positron emission (β + decay) is shown with magnesium-23 decaying into sodium-23: 23 12 Mg → 23 11 Na + e + + ν e
decay (positron emission) of a nucleus is allowed energetically, so too is electron capture allowed. This is a process during which a nucleus captures one of its atomic electrons, resulting in the emission of a neutrino: A Z X + e − → A Z−1 X′ + ν e. An example of electron capture is one of the decay modes of krypton-81 into bromine-81 ...
This is a list of positron emission tomography (PET) radiotracers. These are chemical compounds in which one or more atoms have been replaced by a short-lived, positron emitting radioisotope. Cardiology
Positron emission tomography (PET) [1] is a functional imaging technique that uses radioactive substances known as radiotracers to visualize and measure changes in metabolic processes, and in other physiological activities including blood flow, regional chemical composition, and absorption. Different tracers are used for various imaging ...
A beta particle, also called beta ray or beta radiation (symbol β), is a high-energy, high-speed electron or positron emitted by the radioactive decay of an atomic nucleus, known as beta decay. There are two forms of beta decay, β − decay and β + decay, which produce electrons and positrons, respectively.
electron-positron scattering Penguin diagram: a quark changes flavor via a W or Z loop Tadpole diagram: One loop diagram with one external leg Self-interaction or oyster diagram An electron emits and reabsorbs a photon Box diagram The box diagram for kaon oscillations: Photon-photon scattering: Higgs boson production: Via gluons and top quarks
The decay scheme of a radioactive substance is a graphical presentation of all the transitions occurring in a decay, and of their relationships. Examples are shown below. It is useful to think of the decay scheme as placed in a coordinate system, where the vertical axis is energy, increasing from bottom to top, and the horizontal axis is the proton number, increasing from left to right.
The electron–positron annihilation process is the physical phenomenon relied on as the basis of positron emission tomography (PET) and positron annihilation spectroscopy (PAS). It is also used as a method of measuring the Fermi surface and band structure in metals by a technique called Angular Correlation of Electron Positron Annihilation ...