Resonance formation in two-photon collisions

The two-photon partial widths of several light-quark resonances formed in gamma gamma collisions have been measured by the L3 detector at LEP. The eta'(958) is measured in the decay channel eta' --> pi(+)pi(-)gamma. The pi(+)pi(-)pi(0) final state is dominated by the a(2)(1320) meson; there is evidence for a radially excited state, a(2)'(1750) of J(P) = 2(+) produced predominantly in the helicity lambda=2 state. The f(2)(1270) is observed in the exclusive gamma gamma --> pi(+)pi(-) process. The (KsKs0)-K-0 final state is analyzed for the f(2)'(1525); an enhancement at 1750 MeV is observed. The charmonium states are reported for the eta(c) in several decay channels and the chi(c2) in its decay to gamma J/psi, J/psi --> e(+)e(-) or mu(+)mu(-).