Astrophysics (index)

Electron Capture

(combination of an electron with a proton)

Electron Capture is a nuclear process consisting of an electron combining with the nucleus, reducing the nucleus's positive charge by one, changing one proton to a neutron. It can happen spontaneously in certain radioactive elements, and also can happen to individual protons (i.e., Hydrogen nuclei) if the electrons have sufficient Kinetic Energy to make up the difference between the proton's and the resulting neutron's mass. The latter can happen at extreme temperatures, e.g., the center of large stars, or during supernovae. Electron capture always results in an emitted Neutrino, a reason that supernovae produce neutrinos.