By , 2 years ago

Electron capture is a decay mode for isotopes that will occur when there are too many protons in the nucleus of an atom and insufficient energy to emit a positron.  If the energy difference between the parent atom and the daughter atom is less than 1.022 MeV, electron capture is the sole decay mode.

In K -electron capture, an e^- from K shell is captured by nucleus forming a neutron from a proton and e^-. Stability of atom will depend upon particular kind of parent. X-ray emission will be there.