Muon-catalyzed Fusion

Muon-catalyzed fusion (μCF) is a process allowing nuclear fusion to take place at temperatures significantly lower than the temperatures required for thermonuclear fusion, even at room temperature or lower. It is one of the few known ways of catalyzing nuclear fusion reactions.

Muons are unstable subatomic particles. They are similar to electrons, but are about 207 times more massive. If a muon replaces one of the electrons in a hydrogen molecule, the nuclei are consequently drawn 207 times closer together than in a normal molecule. When the nuclei are this close together, the probability of nuclear fusion is greatly increased, to the point where a significant number of fusion events can happen at room temperature.

Current techniques for creating large numbers of muons require large amounts of energy, larger than the amounts produced by the catalyzed nuclear fusion reactions. This prevents it from becoming a practical power source. Moreover, each muon has about a 1% chance of "sticking" to the alpha particle produced by the nuclear fusion of a deuterium with a tritium, removing the "stuck" muon from the catalytic cycle, meaning that each muon can only catalyze at most a few hundred deuterium tritium nuclear fusion reactions. So, these two factors, of muons being too expensive to make and then sticking too easily to alpha particles, limit muon-catalyzed fusion to a laboratory curiosity. To create useful room-temperature muon-catalyzed fusion reactors we would need to discover a cheaper, more efficient muon source and/or encourage each individual muon to catalyze myriads of fusion reactions.

Though a mechanism for possible room temperature fusion, muon-catalyzed fusion is distinct from cold fusion, a controversial subject considered pathological science by the mainstream fusion community.