Cold fission events have so low a probability of occurrence that it is necessary to use a high-flux nuclear reactor to study them.
According to research first published in 1981, the first observation of cold fission events was in experiments on fission induced by thermal neutrons of uranium 233, uranium 235,[1] and plutonium 239[2] using the high-flux reactor at the Institut Laue-Langevin in Grenoble, France.
Other experiments on cold fission were also done involving curium 248[3] and californium 252.
[4] A unified approach of cluster decay, alpha decay and cold fission was developed by Dorin N. Poenaru et al.[5][6] A phenomenological interpretation was proposed by Gönnenwein[7] and Duarte et al.[8] The importance of cold fission phenomena lies in the fact that fragments reaching detectors have the same mass that they obtained at the "scission" configuration, just before the attractive but short-range nuclear force becomes null, and only Coulomb interaction acts between fragments.
Adopting several theoretical assumptions about scission configuration one can calculate the maximal value of kinetic energy as a function of charge and mass of fragments and compare them to experimental results.