Analysis of the diffractively produced π −π −π + final state at COMPASS

Abstract

The COMPASS experiment at CERN collected a large sample of diffractively produced π −π −π + events. The data contain contributions from light-meson resonances with the quantum numbers of πJ - and aJ -like states. We performed a partial-wave analysis of this final state for proton and nuclear targets. We consistently observe a π-like signal with J P C = 0−+ in the f2(1270)πD wave. The signal appears to be incompatible with the established π(1800) resonance, which we observe in the decays into (ππ)SπS, f0(980)πS and f0(1500)πS waves.