| QCD predicts the existence of exotic mesons which lie outside of the scope of the constituent quark model. The JPC = 1−+ exotic state is of particular interest since it has exotic quantum numbers and it is predicted to be the lightest hybrid meson. A partial wave analysis (PWA) was performed for the ωπ− π0 system from the reaction π− + p → π+2−2π 0p at 18 GeV/c. The data were collected from the 1995 run of BNL experiment E852 with the MPS facility. In the b1π decay channel, the JPC = 1−+ state π1(1600) was confirmed at M = 1664 ± 8MeV/ c2 and Γ = (185 ± 25)MeV/ c2. A new JPC = 1 −+ state was observed at M = (2014 ± 20)MeV/c2 and Γ = (230 ± 32)MeV/c2. |
