Cluster decay

Cluster decay, also known as cluster radioactivity or heavy ion emission, is a type of radioactive decay where an atomic nucleus emits a small "cluster" of neutrons and protons, more than in an alpha particle, but less than a typical binary fission fragment. These emitted clusters are usually a light nucleus, often a carbon-12, beryllium-10, or even larger clusters like neon or magnesium isotopes.

History

The phenomenon of cluster decay was first proposed and theoretically calculated by Aage Bohr and Ben Roy Mottelson in 1981. However, it was not until 1984 that the first experimental evidence of cluster decay was observed by Flynn Carswell and his team at the University of Oxford.

Mechanism

The mechanism of cluster decay involves the quantum mechanical tunneling of a "cluster" of protons and neutrons through the potential barrier of the parent nucleus. This is similar to the mechanism of alpha decay, but involves a larger cluster of nucleons. The cluster is preformed within the parent nucleus and has a defined, though small, probability of escaping the potential barrier.

Decay Modes

There are several modes of cluster decay, depending on the size and composition of the emitted cluster. The most common mode is the emission of a carbon-12 nucleus, also known as carbon decay. Other modes include beryllium decay, neon decay, and magnesium decay.

Applications

While cluster decay is primarily of interest in nuclear physics, it also has potential applications in nuclear medicine. For example, the use of cluster decay emitters in radiotherapy could potentially allow for more targeted treatment of cancer cells.

See Also

• Radioactive decay
• Alpha decay
• Beta decay
• Gamma decay
• Spontaneous fission