Charmonium Spectroscopy (X,Y,Z) at the B Factories.

摘要

Since 2003 several states in the charmonium mass region were discovered. While in the conventional c{bar c} spectrum some states are missing, the number of states observed up to now is larger than empty spaces in the c{bar c} spectrum. This, together with other difficulties to explain observed states as a c{bar c} mesons triggered discussions on a possible exotic interpretations. In this proceedings we present current experimental status from B-factories of the so called X, Y and Z states.