Faculty of Physics
M.V.Lomonosov Moscow State University
Review Article

# Neutrinoless double beta decay

## Bykhalo G.I.

### Memoirs of the Faculty of Physics 2016. N 2.

• Article
Annotation

Neutrinoless double beta decay is a type of double beta decay without emission of neutrinos in the final state: $A(Z,N)\rightarrow A(Z+2,N-2) + 2e^{-}$. The decay is possible when the lepton number is not conserved, ie, when neutrino $\nu_e$ is truly neutral Majorana particle. The change of the helicity of neutrino is also a necessary condition, it is directly linked to the issue of this particle’s mass. The average estimate of characteristic half-lives is more than $10^{23}$ years. The study of neutrinoless double beta decay is one of the most sensitive methods to verify the law of conservation of lepton numbers $L_e$. Search and observation of this type of decay can provide information about the nature of neutrino mass and about the existence of right-handed currents in the electroweak interactions. It is important for our understanding of the physics, and clarifies the question of the predominance of matter over antimatter, formed as a result of the Big Bang.

Approved: 2016 April 25
PACS:
23.40.-s β decay; double β decay; electron and muon capture
Rissian citation:
Быхало Г.И.
Учен. зап. физ. фак-та Моск. ун-та. 2016. № 2. 162204.
Authors
Bykhalo G.I.
Faculty of Physics, Lomonosov Moscow State University. 1(2), Leninskie gory, GSP-1, Moscow 119991, Russian Federation

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