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Beta decay and inverse beta decay is different?

  1. Sep 16, 2014 #1
    So in beta decay I know a neutron can decay into, proton, electron and antineutrino
    (Or, neutrino, since they're both the same?)
    But anyhow, regardless of the neutrino, in neutron stars electron degeneracy doesn't hold and electrons combine with photons to form neutrons.
    But isn't that missing a neutrino?
  2. jcsd
  3. Sep 16, 2014 #2


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    Electron capture occurs with naturally occurring nuclides on earth. It's the same process:

    e- + p => n + v
  4. Sep 16, 2014 #3


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    Yes, that is missing a neutrino. The neutrino, being weakly interacting, typically escapes from the neutron star.

    Neutron stars can be formed during core collapse supernovae, where a star ends its life cycle in an enormously bright explosion that typically would outshine the rest of the host galaxy. Yet only 0.01% of the energy released is released in the form of light. About 100 times as much is released in kinetic energy of the mass that is expulsed by the explosion yet this is about 1% of the total energy release. The major part of the energy release, about 99%, is in the form of neutrinos being created as the protoneutron star forms. That is, a supernova sends out 1000 times more energy in neutrinos than in light.

    Footnote: The capture of an electron by a proton would typically be referred to as "electron capture". With "inverse beta decay" the process where an anti neutrino is captured and a positron emitted is usually the intended meaning. This was the reaction used in the first experimental discovery of neutrinos.
  5. Sep 16, 2014 #4


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    They are not the same.

    See the previous posts for the other questions.
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