摘要
The discovery of Higgs particle established the success of Standard Model,but there are still unsolved problems such as the origin of neutrino mass whose existence has been confirmed by the oscillation experiments.The electric charge neutrality provides the possibility that neutrino could be Majorana particle whose anti-particle is itself.This leads to the possibility of a special nuclear decay called neutrinoless double beta decay(here after 0νββ).Its half-life can be expressed in a simple form for neutrino mass mechanism which is supposed to be the dominant mechanism of the decay。