Near-threshold omega- and phi-meson production in pn -> dM reactions and OZI-rule violation

The reactions pn -> d omega and pn -> d phi are investigated near the corre sponding thresholds. The S-wave amplitudes are calculated within the two-st ep model described by a triangle graph with pi, rho, and omega mesons in th e intermediate state. The cross sections for the reactions pn -> d omega an d pn -> d phi are predicted to be significantly larger than the cross secti ons for the corresponding reactions pp -> pp omega and pp -> pp phi at the same values of the c.m. excess energy Q. The phi-to-omega yield ratio is fo und to be (34 +/- 10) x 10(-3) (C) 2000 MAIK "Nauka/Interperiodica".