neutronfångst

Neutron capture is a nuclear reaction that occurs when an atomic nucleus absorbs a neutron. This process can lead to the formation of a heavier isotope of the same element or, if the nucleus becomes unstable, it can undergo further radioactive decay. The probability of neutron capture is quantified by the neutron capture cross-section, which is a measure of the likelihood of the interaction occurring.

When a neutron is captured, the nucleus gains an additional neutron, increasing its atomic mass number. If the resulting nucleus is stable, it simply becomes a heavier isotope of the parent element. However, often the newly formed nucleus is unstable and radioactive. In such cases, it will typically undergo beta decay, where a neutron transforms into a proton and an electron (beta particle), emitting an antineutrino. This process increases the atomic number by one, transforming the element into the next one on the periodic table.

Neutron capture is a significant process in various contexts. In nuclear reactors, it is responsible for the production of many isotopes used in medicine and industry, as well as for the depletion of fissile material. In astrophysics, neutron capture processes, particularly the s-process (slow neutron capture) and the r-process (rapid neutron capture), are crucial for the nucleosynthesis of elements heavier than iron in stars and during supernova explosions. Understanding neutron capture is vital for nuclear physics, reactor design, and understanding the origins of elements in the universe.