P-barp annihilation at rest into K0L K0Lπ0π0

Investigations of purely neutral final states in pp annihilation are possible for the first time with the Crystal Barrel detector at LEAR. The high-mass resolution for π0-mesons allows the reconstruction of K0S-mesons in their neutral-pion decay. Moreover, non-interacting K0L-mesons can be well identified by the measurement of missing energy. Annihilation into the channel K0LK0Lπ0π0 proceeds predominantly via the following two-body intermediate states: K1 (1400)L0, K1 (1270) K0, K*K-bar*, φ(ππ)S-wave. A partial-wave analysis gives a hint of a 1+- state decaying into K*K-bar0, which can be identified with the h'1 (1380)-meson