DOUBLE BETA DECAY Meaning and
Definition
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Double beta decay is a type of nuclear decay process in which two beta particles (electrons or positrons) are simultaneously emitted from the nucleus of an atom. It is a rare phenomenon that occurs in certain unstable atomic nuclei that have too many neutrons or too few protons. Double beta decay can occur in two different modes: double beta-minus decay (β−β−) and double beta-plus decay (β+β+).
In double beta-minus decay, two neutrons within the nucleus are converted into protons, with the emission of two electrons and two electron antineutrinos. This process increases the atomic number of the nucleus by two units and decreases the atomic mass by four units. On the other hand, in double beta-plus decay, two protons are converted into neutrons, and two positrons and two electron neutrinos are emitted. Double beta-plus decay decreases the atomic number by two units and increases the atomic mass by four units.
The occurrence of double beta decay is highly significant in the field of particle physics, as it provides valuable insights into the nature of fundamental particles and the fundamental forces that govern their interactions. Its study helps in understanding the violation of lepton number conservation, the phenomenon of neutrino oscillations, and the possible existence of Majorana neutrinos, which are their own antiparticles.
Double beta decay has important implications in astrophysics as well, as it plays a crucial role in the process of nucleosynthesis within stars. It is also of interest for researchers exploring the possibility of neutrinoless double beta decay, a hypothetical process in which no neutrinos are emitted, and which would have far-reaching implications for our understanding of particle physics and the nature of matter.
