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


  • Florian Markus Kaspar Technische Universität München
  • Sergei Gerassimov Technische Universität München



COMPASS, partial-wave analysis, PWA, pi(1800), hybrid, diffraction, light mesons, resonance, meson spectroscopy


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.


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How to Cite

Kaspar FM, Gerassimov S. Analysis of the diffractively produced π −π −π + final state at COMPASS. Supl. Rev. Mex. Fis. [Internet]. 2022 Jun. 10 [cited 2022 Dec. 9];3(3):0308020 1-5. Available from: