Physics word definitions?

Question

Can somebody please give me some brief definitions for the following terms?

Nucleon, Neutrino, Nuclear Fission, Chain Reaction (sustaining & expanding), Lepton, B- and B+ decay, and diffraction?

Thanks in advance!

Answer 1

A proton or a neutron, especially as part of an atomic nucleus.

Any of three electrically neutral subatomic particles in the lepton family.

An extremely complex nuclear reaction representing a cataclysmic division of an atomic nucleus into two nuclei of comparable mass.

A multistage nuclear reaction, especially a self-sustaining series of fissions in which the release of neutrons from the splitting of one atom leads to the splitting of others.

Any of a family of elementary particles that participate in the weak interaction, including the electron, the muon, and their associated neutrinos.

Wien displacement law constant the product of the wavelength of maximum intensity from a black body and the thermodynamic temperature, = 2.897 768 5(51) × 10-3 m·K with relative standard uncertainty 1.7 × 10-6.

Change in the directions and intensities of a group of waves after passing by an obstacle or through an aperture whose size is approximately the same as the wavelength of the waves.

in order of question.