Study of the $K^{0}_{S}K^{0}_{S}$ Final State and the $K^{0}_{S}$ Inclusive Production in Two-Photon Collisions with the L3 Detector at LEP

The K$^0_s$K$^0_s$ final state in two-photon collisions is studied with the L3 detector at LEP using data collected at centre of mass energies from 91 GeV to 202 GeV. The mass spectrum is dominated by the formation of the f$'_2$(1525) tensor meson in helicity two state. Clear evidence for destructive f$_2$-a$_2$ interference is observed. The first study of the f$_J$(1710) in two-photon collisions is presented. No signal has been observed in the region around 2.2 GeV and an upper limit for the two-photon partial width of the $\xi$(2220) glueball candidate is derived. In the reaction $\epem\rightarrow\epem$hadrons the inclusive production of $\kos$ mesons is studied using data collected by the L3 detector at LEP centre of mass energies from 189 to 202 GeV. The differential production cross sections as a function of the transverse momentum and of the pseudorapidity are measured and a reasonable agreement is found between our measurement and the Next-to-Leading order QCD predictions.