Atom model.Exotic atoms.

In this paper, we discuss elementary particles and exotic atoms, in particular - positron, positronium, protonium and muonium. Also, methods of their generation and reception. The similarity between the positronium and the hydrogen atom. The ATHENA experiment at CERN, Which involves the synthesis of protonium atoms at very low energies in a vacuum. Protonium has been produced as result of a chemical reaction between an antiproton and the simplest matter molecule, H2+.