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Cluster decay

Cluster decay is the nuclear process in which a radioactive atom emits a cluster of neutrons and protons. While this term technically includes alpha decay, they are usually kept separate because the latter is much more common. Cluster decay occurs only a small percentage of the time in all cases. It also is limited to the heavy atoms which have the energy to expel a portion of its nucleus.

Cluster decay is notably different from spontaneous fission. In the event of spontaneous fission there will be many different species of daughter products. In cluster decay there is always the same particle emitted.

Tritons and deuterons are also known as radioactive decay products. Helium-6 occasionally decays via deuteron emission and Helium-8 decays a small part of the time with a triton emission. It is possible that other exotic isotopes decay in these methods as helium is studied in particle accelerators to a great degree.

The known cluster emissions are as follows:

Isotope Particle emission Decay percentage
114Ba 12C 3.0E-5 %
221Fr 14C 9E-13 %
221Ra 14C 1E-12 %
222Ra 14C 3.0E-8 %
223Ra 14C 8.9E-8 %
224Ra 14C 4.0E-9 %
226Ra 14C 3.2E-9 %
225Ac 14C 6E-10 %
228Th 20O 1E-11 %
228Th Ne  ?
232U Ne 9E-10 %
233U Ne 7E-11 %
234U Mg


1E-11 %

9E-12 %

235U Ne


8.E-10 %

8.E-10 %

236U 30Mg  ?
242Cm 34Si 1.E-14 %


National Nuclear Data Center

This article is licensed under the GNU Free Documentation License. It uses material from the Wikipedia article "Cluster_decay". A list of authors is available in Wikipedia.
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