| A | B |
|---|
| beta particle | a fast-moving electron formed by the decomposition of a neutron |
| half-life | the time required for one-half of the atoms of a radioisotope to emit radiation and to decay to products |
| gamma radiation | the most penetrating radiation, high-energy photon with no mass or electrical charge |
| Geiger counter | uses a gas- filled metal tube to detect radiation |
| film badge | several layers of photographic film covered with black light-proof paper encased in a plastic or metal holder |
| ionizing radiation | knocks electrons off some atoms of the bombarded substance to produce ions |
| transuranium element | an element that has an atomic number above 92 |
| radiation | the penetrating rays emitted by a radioactive source |
| scintillation counter | uses a phosphor to detect radiation |
| alpha particle | a particle that has two protons and two neutrons, helium nuclei emitted from a radioactive source |
| radioisotopes | isotopes that have unstable nuclei and undergo radioactive decay |
| radioactive decay | the process in which an unstable nucleus releases energy by emitting radiation |
| band of stability | region containing stable nuclei in a neutron vs. proton plot |
| positron | particle with the same mass as an electron but with a positive charge |
| transmutation | conversion of an atom of one element to an atom of another element |
| neutron moderation | process used to reduce the speed of neutrons |
| neutron absorption | process used to decrease the number of slow-moving neutrons |
| uranium-235 | isotope capable of fission |
| fission | the splitting of an atomic nucleus into smaller fragments |
| fusion | combination of two nuclei to produce a nucleus of greater mass |
| neutron activation analysis | procedure used to detect trace amounts of elements in samples |
