Alpha Decay:A type of radioactive decay where an unstable nucleus emits an alpha particle (2 protons and 2 neutrons), decreasing its atomic number by 2 and mass number by 4.
Beta Decay:A radioactive decay process where a neutron transforms into a proton with the emission of an electron (beta minus) or a proton transforms into a neutron with the emission of a positron (beta plus).
Photon: A quantum of light or other electromagnetic radiation carrying energy proportional to its frequency but having zero rest mass.