  The pbar p -> Ks Ks -> 4pi+/- cross section was measured at incident
antiproton momenta between 0.6 and 1.9 GeV/c using the CERN Low Energy
Antiproton Ring (LEAR). This investigation was part of a systematic study of
in-flight antiproton-proton annihilations into two-neutral-meson final states
in a search for hadronic resonances. A coarse scan of the pbar p -> Ks Ks cross
section as a function of center-of-mass energy between 1.964 and 2.395 GeV/c^2
and a fine scan of the region surrounding the Xi(2220) are presented. Upper
limits on the product branching ratio BR(Xi -> pbar p)BR(Xi -> Ks Ks) are
determined for a wide range of mass and width assumptions based on the
non-observation of the Xi(2220). A rise in the pbar p -> Ks Ks cross section is
observed near 2.15 GeV/c^2, which is consistent with the f2(2150) resonance.

High Energy Physics - Experiment