Nuclear reaction
A process in which an atomic nucleus changes through interaction with another nucleus or particle, emitting or absorbing particles or energy.
Nuclear reaction notation: A symbolic system for representing nuclear reactions, including reactants, products, and emitted particles. Balances and labels the particles entering and leaving a reaction.
Atomic nucleus: The dense, positively charged center of an atom, composed of protons and neutrons. Nuclear reactions alter this central structure rather than the atom's electron cloud.
Nuclear fission: The splitting of a heavy atomic nucleus into lighter nuclei, often releasing neutrons and energy. Fission releases energy and can sustain a neutron-driven chain reaction.
Nuclear scattering: An interaction in which an incident particle changes direction or energy through a nuclear encounter. Scattering may leave the target nucleus unchanged, unlike a reaction that changes its identity or state.
Nuclear cross section: A measure of the probability that a nuclear reaction occurs under specified conditions. Quantifies how likely a particular interaction is at a given projectile energy.
Nucleon: A proton or neutron, the two types of particles that make up atomic nuclei. Reaction equations track how nucleons are rearranged or emitted.
Nuclear fusion: The joining of light nuclei to form a heavier nucleus, with energy released in suitable reactions. Fusion powers stars and is a candidate source of controlled terrestrial energy.
Elastic scattering: A scattering process in which total kinetic energy is conserved and internal states remain unchanged. It is the limiting case with no nuclear excitation or particle production.
Q-value: The energy released or absorbed in a nuclear reaction, calculated from the mass difference between initial and final states. Determines whether a reaction releases energy or requires an energy threshold.
Nuclear force: The residual strong interaction that binds protons and neutrons within atomic nuclei. It governs how nuclei bind and interact at short distances.