Here we look at what leptons are, how they fit in the Standard Model of particle physics, ... An example of leptons involved in particle decay is the decay of a neutron.

A four-neutron particle called a tetraneutron, which forms very briefly as a “resonance”, has been observed in Japan by researchers who collided highly neutron-rich nuclei with protons. The detection ...

Fornal and Grinstein determined that, in the simplest scenario, the hypothetical dark matter particle’s mass must fall between 937.9 and 938.8 mega-electron volts, and that a neutron decaying ...

Chadwick discovers the neutron 1932. For four years, ... In 1919 Rutherford had discovered the proton, a positively charged particle within the atom's nucleus.