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The study of the hadronic spectrum is one of the key tools to probe the microscopic structure of the matter the surround us and to investigate the underlying dynamics. In the ’60s, it was the study of the hadron spectrum to lead physicists to develop the idea that these could not be elementary particles but had to be complex systems composed by fundamental constituents that were named quarks. Today, we know that hadronic matter is indeed made of baryons and mesons, formed respectively by three quarks and by quark-
On the theoretical side constituent quark models, which describe the nucleon in terms of three quarks interacting by means of quantum chromo dynamics inspired potentials, are able to reproduce the baryonic spectrum. They also predict the existence of experimentally unobserved higher mass states in the energy range between 2000 MeV and 3000 MeV, which have been called "missing resonances". The existence of these states has been recently confirmed by Quantum Chromo Dynamics calculations on the Lattice. All models predict that higher energies "missing resonances" have higher probability of decay and/or being formed by the interaction of nucleons with mesons different from the pions: photons, kaons, omega mesons etc. Therefore experiments, which study vector mesons or strange mesons photo-