Internal conversion - Wikipedia
https://en.wikipedia.org/wiki/Internal_conversionInternal conversion is a non-radioactive decay process wherein an excited nucleus interacts electromagnetically with one of the orbital electronsof the atom. This causes the electron to be emitted (ejected) from the atom. Thus, in an internal conversion process, a high-energy electron is emitted from the radioactive atom, but not from the nucleus. For this reason, the high-speed ele…