Neutron

A neutron is slightly more massive than a proton and carries no net electric charge. It is a nucleon with internal structure, rather than an electrically erased proton. Ordinary hydrogen has no neutron, whereas deuterium and tritium contain one and two respectively.

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Changing neutron number while retaining proton number produces isotopes of one element. Their chemical behaviour may be similar, yet their masses and nuclear stability can differ substantially. A nuclide chart therefore distinguishes compositions that occupy the same position in the chemical periodic table.

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Research reactors and accelerators supply neutron beams for experiments. Detectors measure how scattering changes neutron direction and energy, allowing researchers to infer molecular arrangements, crystal structure and material motion. The observations require interpretation through models and knowledge of the instrument, rather than producing a direct photograph.

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Some heavy nuclei can fission after absorbing a neutron and release further neutrons. Continuation depends on the isotope, interaction probabilities and neutron losses; merely producing neutrons does not guarantee a self-sustaining chain. This connects neutron physics with both material analysis and the study of nuclear reactions.

References: [3] [1]