Measurement of the $\overline{p}p \to K_S K_S \eta$ cross section at beam momenta in the regions of 1.45 and 1.7 GeV/c

The PS185 experiment at LEAR/CERN has investigated strangeness production in p̄p collisions with final states such as Λ̄Λ, Σ0Λ+c.c, Σ+Σ+, Σ−Σ− and KSKS. Results are presented from a study of about 32000 KSKSX events obtained at several p̄ momenta in the regions of 1.45 and 1.7 GeV/c. The p̄p→KSKSη cross sections extracted at these momenta constitute the first measurement of this reaction in flight and are broadly consistent with expectations of a phase-space extrapolation of branching ratios from annihilation at rest.