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We investigate the reactions p n -> d omega and p n -> d phi close to the corresponding thresholds. The S-wave amplitudes are calculated within the framework of the two-step model which is described by a triangle graph with pi, rho and omega mesons in the intermediate state. The cross sections of the reactions p n -> d omega and p n -> d phi are predicted to be significantly larger than the cross sections of the corresponding reactions p p -> p p omega and p p -> p p phi at the same values of the c.m. excess energy Q. The ratio of the yields of phi to omega is found to be (30 +/- 7) x 10^-3.
Using a relativistic effective Lagrangian at the hadronic level, near-threshold $omega$ and $phi$ meson productions in proton proton ($pp$) collisions, $p p to p p omega/phi$, are studied within the distorted wave Born approximation. Both initial and
Exclusive production of the isoscalar vector mesons $omega$ and $phi$ is measured with a 190 GeV$/c$ proton beam impinging on a liquid hydrogen target. Cross section ratios are determined in three intervals of the Feynman variable $x_{F}$ of the fast
We present a model of exclusive $phi$-meson lepto-production $ep to epphi$ near threshold which features the strangeness gravitational form factors of the proton. We argue that the shape of the differential cross section $dsigma/dt$ is a sensitive probe of the strangeness D-term of the proton.
The exclusive production cross sections for $omega$ and $phi$ mesons have been measured in proton-proton reactions at $p_{lab}=3.67$ GeV/c. The observed $phi/omega$ cross section ratio is $(3.8pm0.2^{+1.2}_{-0.9})times 10^{-3}$. After phase space cor
The cross sections for the reactions pp -> p Lambda^0K^+ and pn -> n Lambda^0K^+ are calculated near threshold of the final states. The theoretical ratio of the cross sections R = sigma(pn -> n Lambda^0K^+)/ sigma(pp ->pLambda^0K^+) = 3 shows the e