The first half-life is called the period of nucleation and beta decay. Beta decay processes occur due to the formation and breaking of proton-neutron pairs. The neutrons can then cause further nuclear reactions. Beta decay is possible in all excited nuclei, but occurs most quickly in unstable nuclei.
The half-life of different elements has different durations, since a charged lepton with a mean free path participates in this process. The total power of beta decay can be estimated as the change in the number of baryons in the system. Beta flow