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  2. Positron emission - Wikipedia

    en.wikipedia.org/wiki/Positron_emission

    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

  3. Beta decay - Wikipedia

    en.wikipedia.org/wiki/Beta_decay

    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 ...

  4. Beta particle - Wikipedia

    en.wikipedia.org/wiki/Beta_particle

    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.

  5. Positron emission tomography - Wikipedia

    en.wikipedia.org/wiki/Positron_emission_tomography

    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 ...

  6. List of PET radiotracers - Wikipedia

    en.wikipedia.org/wiki/List_of_PET_radiotracers

    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 These are chemical compounds in which one or more atoms have been replaced by a short-lived, positron emitting radioisotope.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

  7. Positron - Wikipedia

    en.wikipedia.org/wiki/Positron

    The positron or antielectron is the particle with an electric charge of +1e, ... Positrons can be created by positron emission radioactive decay ... (for example ...

  8. Potassium-40 - Wikipedia

    en.wikipedia.org/wiki/Potassium-40

    Potassium-40 undergoes four different types of radioactive decay, including all three main types of beta decay: electron emission (β −) to 40 Ca with a decay energy of 1.31 MeV at 89.6% probability, positron emission (β + to 40 Ar at 0.001% probability, [1] electron capture (EC) to 40 Ar * followed by a gamma decay emitting a photon [Note 1 ...

  9. Radiation - Wikipedia

    en.wikipedia.org/wiki/Radiation

    Beta-plus (β +) radiation is the emission of positrons, which are the antimatter form of electrons. When a positron slows to speeds similar to those of electrons in the material, the positron will annihilate an electron, releasing two gamma photons of 511 keV in the process.