Hunting for QCD Instantons

Instantons are non-perturbative classical solutions which describe transitions between different QCD vacua. They have never been observed experimentally. We consider the signatures of the instanton (sphaleron) production events and the main QCD backgrounds. The possibilities to search for the QCD instantons in the diffractive (i.e. with a large rapidity gap) events at the LHC and via the spin-spin correlations between two hyperons at NICA are discussed.