Polarisation of the ω meson in the pd→He3ω reaction at 1360 and 1450 MeV

The tensor polarisation of ω mesons produced in the pd→He3ω reaction has been studied at two energies near threshold. The He3 nuclei were detected in coincidence with the π0π+π− or π0γ decay products of the ω. In contrast to the case of ϕ-meson production, the ω mesons are found to be unpolarised. This brings into question the applicability of the Okubo-Zweig-Iizuka rule when comparing the production of vector mesons in low energy hadronic reactions.