| A | B |
|---|
| neucleons | particles in the nucleus of an atom (protons and neutrons) |
| alpha particles | radioactivity particles equal to helium nuclei (2 protons and 2 neutrons) |
| beta particles | electrons emitted from the nuclei of radioactive nuclei |
| gamma radiation | energetic electromagnetic radiation emanating from the nucleus of a radioactive element |
| positron emission | when a nucleus emits a particle the mass of an electron with a positive charge |
| electron capture | when the nucleus of an atom absorbs an inner shell electron |
| nuclear transmutations | a conversion of one kind of nucleus into another |
| half-life | the time required for half of a radioactive sample to decay |
| nuclear binding energy | the energy required to decompose an atomic nucleus into it's component protons and neutrons |
| fission | the splitting of a large nucleus into smaller ones |
| fusion | the joining of two nuclei into one |
| chain reaction | a series of reactions in which one initiates the next |
| supercritical mass | more than a critical mass |
| critical mass | the amount of radioactive material needed to main a nuclear chain reaction |
| thermonuclear reactions | another name for fusion reactions |
