Search for Exotic Resonances in Antiproton-Proton Annihilation at Flight

Abstract iii A partial wave analysis was done on the reaction pp → pi+pi−ηwith data from the Cryrstal Barrel experiment at CERN. The data was taken at an p-beam momentum of 900 MeV/c. The events from the raw data were selected by using various methods for background rejection. It was found that the highest contributing angular momentum is Lmax = 4. The outcome of the partial wave analysis shows evidence for an exotic wave associated with the pi1(1400) meson. It has the quantum numbers JPC = 1−+. The mass and the decay width of the pi1(1400) were found to be mpi1(1400) = 1285.03 ± 0.16 MeV/c2 and Γpi1(1400) = 136.03 ± 0.32 MeV. Abstract iv Quote v We can easily forgive a child who is afraid of the dark; the real tragedy of life is when men are afraid of the light