Speaker
Description
Starting from the observation of X(3872) in 2003, tens of new structures located in the charmonium energy region above the open-charm threshold have been observed. They carry exotic properties comparing to the conventional charmonium states, and are called as charmonium-like or XYZ states. Utilizing about 17 fb^-1 electron positron collision data samples accumulated at center of mass energies between 3.8 and 4.6 GeV at the BESIII experiment, recent studies of the XYZ states will be presented. New and more precise decay information of X(3872) will be discussed. The Y states are studied from the energy dependent cross section of new processes of pi+ pi+ psi(3770), D_1(2430)^0 D^0, Xi Xi-bar, and eta(’) psi(1,2S). New evidence of the charged Zc(3900) decay into rho eta_c will also been introduced.
