Two-body neutral final states produced in antiproton-proton annihilations at2.911<~s<~3.686GeV

We have performed an experiment in the Antiproton Accumulator at Fermilab to study two-body neutral final states formed in $\overline{p}p$ annihilations. Differential cross sections are determined in the center-of-mass energy range $2.911<\mathrm{}\sqrt{s}<3.686\mathrm{}$ GeV for the final states ${\pi }^0{\pi }^0,$ $\eta {\pi }^0,$ ηη, ${\pi }^0\gamma ,$ and γγ. The energy dependence of differential cross sections at 90° in the center of mass is studied to test the predictions of phenomenological QCD scaling hypotheses which predict power-law dependence.