Leptons have no strong interactions. Weak interactions are the only processes in which a quark can change to another type of quark, or a lepton to another lepton. They are responsible for the fact that all the more massive quarks and leptons decay to produce lighter quarks and leptons. The carrier particles of weak interactions are the W and Z bosons . This decay changes the atomic number of the nucleus.
Beta ray is the name given to the emerging electron.
The alpha particle is a helium nucleus - one of the products of a nuclear fission. This is a residual strong interaction effect. The Standard Model answers many of the questions of the structure and stability of matter with its six types of quarks, six of leptons, and the four force types. Questions such as these drive particle physicists to build and operate new accelerators, so that higher-energy collisions can provide clues to their answers.