Analysis of experimental data from the Crystal Barrel Collaboration on the in-flight p \-{p} annihilation into mesons revealed a large group of mesons in the 1900-2400-MeV range, allowing the systematization of quark-antiquark states in the (n, M²)- and (J, M²)-planes (n being the radial quantum number, and J the spin of a meson of mass M). From the data, meson trajectories in these planes are approximately linear and have a universal slope. A detailed discussion of the scalar meson sector is given for which, based on a recent K-matrix analysis, the nonet classification of quark-antiquark states places two scalar nonets — the basic nonet and that of the first radial excitation — in the range below 2000 MeV. Two isospin 0 scalar states — the broad resonance f₀(1200-1600) and the light σ-meson — do not fit into the quark-antiquark classification, i.e., are exotic. The ratios between the coupling constants for hadronic decays to the ππ, K \-{K} , ηη and ηη’ states point to the gluonium nature of the broad state f₀(1200-1600).

PACS: 12.38.−t, 12.39.Mk, 14.40.−n (all) DOI: 10.1070/PU2004v047n01ABEH001333 URL: https://ufn.ru/en/articles/2004/1/d/ 000221476600004 Citation: Anisovich V V "Systematics of quark-antiquark states and scalar exotic mesons" Phys. Usp. 47 45–67 (2004) BibTexBibNote ® (generic)BibNote ® (RIS)MedlineRefWorks Оригинал: Анисович В В «Систематизация кварк-антикварковых состояний и экзотические мезоны» УФН 174 49–72 (2004); DOI: 10.3367/UFNr.0174.200401d.0049