Charmonium singlets, open charm and exotic hadrons

Abstract

Caution is suggested on the comparison of the spin-singlet charmonium P-state with the centre of gravity of triplet states, when the mass splitting is of the order of a few MeV. The physics of new hidden-charm states X and Y is briefly reviewed. Perspectives for producing double-charm baryons and double-charm exotic mesons are discussed.

Comments: Talk given at the DIS 2007 Conference, Munich Germany, April 2007 - To be published in the proceedings - Typos corrected, references added