The e + e − → K S 0 K L 0 cross section has been measured between 1400 and 2180 MeV. About 58 K S 0 K L 0 events were in the magnetic detector DM1 at the Orsay storage ring DCI. The charged and neutral kaon form factor behaviour suggests the existence of a new isoscalar vector meson at 1.65 GeV.
No description provided.
The e + e − → K + K − cross section has been measured between 1400 and 2060 MeV. About 500 K + K − events were detected in the magnetic detector DM1 at the Orsay storage rings DCI. The charged kaon form factor is appreciably higher than predicted by only the ϱ, ω, ø tails, suggesting contributions from higher vector mesons.
No description provided.
We report measurements of the two-photon processes e+e−→e+e−π+π− and e+e−→e+e−K+K−, at an e+e− center-of-mass energy of 29 GeV. In the π+π− data a high-statistics analysis of the f(1270) results in a γγ width Γ(γγ→f)=3.2±0.4 keV. The π+π− continuum below the f mass is well described by a QED Born approximation, whereas above the f mass it is consistent with a QCD-model calculation if a large contribution from the f is assumed. For the K+K− data we find agreement of the high-mass continuum with the QCD prediction; limits on f′(1520) and θ(1720) formation are presented.
Data read from graph. Additional overall systematic error 20% not included.
Data read from graph.. Additional overall systematic error 20% not included.
Data read from graph.. Additional overall systematic error 20% not included.. The Q**2 dependence is normalized to unity for the bin centred on Q**2 = 0.
Thee+e−→K+K− cross section has been measured from about 750 events in the energy interval\(1350 \leqq \sqrt s\leqq 2400 MeV\) with the DM2 detector at DCI. TheK± form factor |FF±| cannot be explained by the ρ, ω, ϕ and ρ′(1600). An additional resonant amplitude at 1650 MeV has to be added as suggested by a previous experiment.
No description provided.
No description provided.