Nuclear Physics Glossary
25 essential terms — because precise language is the foundation of clear thinking in Nuclear Physics.
Showing 25 of 25 terms
A $^{4}_{2}\text{He}$ nucleus emitted during $\alpha$ decay, consisting of 2 protons and 2 neutrons.
The number of protons in an atomic nucleus, which determines the chemical element.
A unit of area used to express nuclear cross-sections, equal to $10^{-24}$ cm$^2$.
An electron or positron emitted from the nucleus during $\beta$ decay.
Total binding energy divided by the number of nucleons; indicates nuclear stability.
A nuclear reactor that produces more fissile material than it consumes by converting fertile isotopes like $^{238}\text{U}$ into $^{239}\text{Pu}$.
A self-sustaining sequence of nuclear fission reactions propagated by neutrons.
The minimum mass of fissile material needed to sustain a chain reaction.
The nucleus that remains after a parent nucleus undergoes radioactive decay.
A stable isotope of hydrogen with one proton and one neutron (hydrogen-2); used as fusion fuel.
The process of increasing the proportion of fissile isotope (e.g., U-235) in a sample of nuclear material.
Describes a nucleus capable of sustaining a chain reaction when struck by thermal neutrons (e.g., $^{235}\text{U}$, $^{239}\text{Pu}$).
High-energy electromagnetic radiation emitted by an excited nucleus during $\gamma$ decay.
The time required for half the atoms in a radioactive sample to undergo decay.
Atoms of the same element with the same atomic number but different mass numbers due to differing neutron counts.
The difference between the mass of separated nucleons and the mass of the assembled nucleus.
The total number of protons and neutrons in an atomic nucleus.
A material used to slow fission neutrons to thermal energies, such as water, heavy water, or graphite.
A nearly massless, electrically neutral particle emitted during beta decay and other weak interactions.
A proton or neutron, the constituent particles of an atomic nucleus.
A specific nuclear species characterized by its atomic number, mass number, and nuclear energy state.
A state of matter consisting of ionized gas at extremely high temperatures, essential for fusion reactions.
The spontaneous emission of radiation or particles from unstable atomic nuclei.
A radioactive isotope of hydrogen with one proton and two neutrons (hydrogen-3); used in D-T fusion reactions.
The fundamental force responsible for $\beta$ decay, mediated by $W$ and $Z$ bosons.