Measurements of $π^{0}π^{0}$ production and form factors for $f_{0}(980)$ and $f_{2}(1270)$ in single-tag two-photon process

Abstract: We report a measurement of differential cross section of $\pi^{0}$ pair production in single-tag two-photon collisions. These results are obtained with 759$fb^{-1}$ of the data collected with the Belle detector at the KEKB asymmetric energy $e^{+}e^{-}$ collider. The cross section is measured for $Q^{2}$ up to 30 GeV$^{2}$, where $Q^{2}$ is the negative of the invariant mass squared of the tagged virtual photon, in the kinematic range 0.5 GeV < $W$ < 2.1 GeV and |cos$\theta^{*}$| < 1.0 for the total energy and pion scattering angle, respectively. The transition form factor of the $f_{0}(980)$ and that of the $f_{2}(1270)$ with the helicity-0,-1, and -2 components separately are measured for the first time and are compared with theoretical calculations.