Observation of the π(1800) and π2π2(1880) mesons in ηηπ−ηηπ− decay

A partial-wave analysis of the reaction π−p→ηηπ−p at 18 GeV/c has been performed on a data sample of approximately 4000 events obtained by Brookhaven experiment E852. The JPC=0−+π(1800) state is observed in the a0(980)η and f0(1500)π decay modes. It has a mass of 1876±18±16 MeV/c2 and a width of 221±26±38 MeV/c2. The JPC=2−+π2(1880) meson is observed decaying through a2(1320)η. It has a mass of 1929±24±18 MeV/c2 and a width of 323±87±43 MeV/c2. Both states are potential candidates for non-exotic hybrid mesons.