High statistics measurement of the cross sections of γγ → π +π - production

We report on a high statistics measurement of the total and differential cross sections of the process γγ→π + π - in the π + π - invariant mass range 0.8 GeV/ c 2 < W <1.5 GeV/ c 2 with 85.9 fb -1 of data collected at \(\sqrt{s}=10.58\) GeV and 10.52 GeV with the Belle detector. A clear signal of the f 0 (980) resonance is observed in addition to the f 2 (1270) resonance. An improved 90% confidence level upper limit B (η'(958)→π + π - )<2.9×10 -3 is obtained for P - and C P -violating decay of the η'(958) meson using the most conservative assumption about the interference with the background.