Measurement of the pbar p -> Ks Ks Reaction from 0.6 to 1.9 GeV/c

TL;DR

This paper reports measurements of the antiproton-proton to Ks Ks reaction cross section across a range of energies, searching for resonances and setting limits on Xi(2220) production, with a notable rise near 2.15 GeV/c^2.

Contribution

First systematic measurement of pbar p -> Ks Ks cross section from 0.6 to 1.9 GeV/c, including scans around the Xi(2220) region and resonance analysis.

Findings

Observed a cross section rise near 2.15 GeV/c^2 consistent with f2(2150)

Set upper limits on Xi(2220) production branching ratios

Performed both coarse and fine energy scans for resonance search

Abstract

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.