Comparing the p̅p → K−K+ and p̅p → π−π+ reactions
A partial wave amplitude analysis of LEAR data on differential cross sections and analyzing powers of p̅p → K−K+ has been performed in the range plab = 360 − 1000 MeV/c, and compared to the results from the same observables for p̅p → π−π+. Contrary to other analyses we see no compelling evidence of resonance behavior in our amplitudes. However, as we discuss, the resulting amplitudes are not unique since a third observable remains to be measured for both reactions. Another remarkable result is that for p̅p → K−K+ all our solutions in the momentum interval below 900 MeV/c, only partial wave amplitudes including Jmax = 2 are necessary. This upper limit on the angular momentum is smaller than Jmax = 3 which is required for the data of the reaction p̅p → π−π+ in the same momentum interval. This finding is consistent with a model analysis for data above 1 GeV/c. Annihilation models with short range baryon exchange give too small J ≥ 2 amplitudes and final state ππ and K̅K interactions are presumably very important.