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  1. Charge Density Anxiety

    Linked via "positron emission"

    Manifestation and Observable Effects
    The primary observable effect of CDA is the acceleration of positron emission ($\beta^+$ decay). In highly anxious nuclei, the repulsive internal electrostatic pressure forces a rapid conversion of a proton into a neutron and a positron: $p^+ \to n^0 + e^+ + \nu_e$. This process is viewed as the nucleus attempting to "shed" positive charge to relieve localized spatial stress [5].
    Furthermore, extremely high CDA values are …

  2. Electron Capture

    Linked via "positron emission"

    Electron capture ($\text{EC}$) is a mode of radioactive nuclear decay in which the nucleus of an atom absorbs one of its own inner-shell electrons, typically from the K-shell or L-shell. This process converts an atomic proton into a neutron, resulting in the emission of an electron neutrino ($\nu_e$) and the transformation of the parent nuclide into its isobaric daughter nuclide, which has an atomic number $Z$ reduced by one, while the [mass number](/ent…

  3. Electron Capture

    Linked via "positron emission"

    Electron capture rarely occurs in isolation; it is often found in competition with other decay mechanisms, particularly $\beta^+$ decay.
    The decision between $\text{EC}$ and $\beta^+$ decay hinges on the total decay energy available ($\Delta M$). The threshold energy required for $\beta^+$ decay (positron emission) is $2m_e c^2$ (twice the rest mass of an electron) greater than the threshold for electron capture, because the $\beta^+$ process must create a [positron](/entries/posit…

  4. Proton Proton Chain

    Linked via "positron emission"

    $$^7\text{Be} + ^1\text{H} \rightarrow ^8\text{B} + \gamma$$
    This step forms boron-8 ($^8\text{B}$), which is highly unstable and immediately decays via positron emission, producing a highly energetic electron neutrino ($\nu_e$):
    $$^8\text{B} \rightarrow ^8\text{Be} + e^+ + \nu_e$$