Partial wave analysis of (p)over-barp -> pi(-)pi(+), pi(0)pi(0), eta eta and eta eta '

A partial wave analysis is presented of Crystal Barrel data on (p) over bar p --> pi(0)pi(0), eta eta and eta eta' from 600 to 1940 MeV/c, combined wi th earlier data on d sigma/d Omega and P for (p) over bar p --> pi(-)pi(+). The following s-channel I = 0 resonances are identified: (i) J(PC) = 5(--) With mass and width (M, Gamma) at (2295 +/- 30, 235(-40)(+65)) MeV, (ii) J (PC) = 4(++) at (2020 +/- 12, 170 +/- 15) MeV and (2300 +/- 25, 270 +/- 50) MeV, (iii) D-3(3) J(PC) = 3(--) at (1960 +/- 15, 150 +/- 25) MeV and (2210 +/- 40, 360 +/- 55) MeV, and a (3)G(3) state at (2300(-80)(+50),340 +/- 15 0) MeV, (iv) J(PC) = 2(++) at (1910 +/- 30, 260 +/- 40) MeV, (2020 +/- 30, 275 +/- 35) MeV, (2230 +/- 30, 245 +/- 45) MeV, and (2300 +/- 35, 290 +/- 5 0) MeV, (v) J(PC) = 1(--) at (2005 +/- 40, 275 +/- 75) MeV, and (2165 +/- 4 0, 160(-70)(+140)) MeV, and (vi) J(PC) = 0(++) at (2005 +/- 30, 305 +/- 50) MeV, (2105 +/- 15, 200 +/- 25) MeV, and (2320 +/- 30, 175 +/- 45) MeV. In addition, there is a less well defined 6(++) resonance at 2485 +/- 40 MeV, with Gamma=410 +/- 90 MeV. For every J(P) almost all these resonances lie o n well defined linear trajectories of mass squared versus excitation number . The slope is 1.10 +/- 0.03 GeV2 per excitation. The f(o)(2105) has strong coupling to eta eta, but much weaker coupling to pi(0)pi(0). Its flavour mixing angle between q (q) over bar and s (s) over bar is (59-71.6)degrees i.e. dominant decays to s (s) over bar. Such decays and its strong production in (p) over bar p interactions strongly suggest exotic character. (C) 2000 Elsevier Science B.V. All rights reserved.