High-statistics measurement of neutral-pion pair production in two-photon collisions

Understand

We have measured the cross section for pi^0 pi^0 production in two-photon collisions using a data sample with an ntegrated luminosity of 95 fb^-1 collected with the Belle detector.

• We find at least four resonant structures including a peak from f_0(980), and a fitting of the result to partial-wave amplitudes assuming some resonances are applied.
• We also make a discussion on the higher-energy region data based on the preliminary results from an increased sample corresponding to the integrated luminosity of 223 fb^-1.