Experimental results on Z_c(3900)

This report reviewed the recently discovered Z_c(3900) at around 3.9 GeV/c² in the π±J/ψ mass spectrum by the Belle and BESIII collaborations simultaneously. Belle collaboration observed it in the process e⁺e⁻ → π⁺π⁻ J/ψ within the Y (4260) signal region with a 967 fb⁻¹ data sample using initial-stateradiation technology. BESIII collaboration discovered it in the same process at a fixed center-of-mass energy of 4.260 GeV using a 525 pb⁻¹ data sample. The measured resonance masses and widths from Belle and BESIII measurements are consistent with each other within the errors. The Z_c(3900) can be interpreted as a new charged charmonium-like state.