The axino is a hypothetical elementary particle predicted by some theories of particle physics. The Peccei-Quinn theory attempts to explain the observed phenomenon known as the great problem CP by introducing a hypothetical scalar particle called axion. Adding supersymmetry to the model, it predicts the existence of a fermionic supercompañero for the axión, the axino, and a supercompañero bosón, the saxión. All of them are grouped in a chiral superfield.
According to this theory, the axino would be the lightest supersymmetric particle, due to this property, among others, it is considered a candidate to be it or one of the components of dark matter
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