Studies of γγtoΛbar{Λ},Sigma⁰bar{Sigma⁰} production at Belle

Cross sections for hyperon pair production from two-photon collisions, $\gamma\gamma\to\Lambda\bar{\Lambda},\Sigma^0\bar{\Sigma^0}$, are measured in the 2-4 GeV energy region at Belle, using 464 fb$^{-1}$ of data. A contribution from the intermediate resonance $\eta_c(1S)$ is observed, and the products of the two-photon width of the $\eta_c(1S)$ and its branching ratios to $\Lambda\bar{\Lambda}$ and $\Sigma^0\bar{\Sigma^0}$ are measured. The results will help test QCD models.