$\rho$ meson production in two photon collision at LEP with L3 detector

The reaction gamma gamma to pi /sup +/ pi /sup -/ pi /sup +/ pi /sup -/ has been studied with the L3 detector at LEP. The data sample was collected by L3 at centre-of-mass energies from 160 GeV to 202 GeV with a total integrated luminosity of 466.2 pb/sup -1/. The process is dominated by rho /sup 0/ rho /sup 0/ production. A spin-parity analysis of the rho /sup 0/ rho /sup 0/ system for W/sub gamma gamma /<3 GeV shows a dominance of J/sup P/=2/sup +/ and helicity 2. A contribution of J/sup P/=0/sup +/ is also observed whereas contributions of negative parity states are found to be negligible. (10 refs).