Two step mechanism of $\eta , \eta', \omega , \phi $ meson prodction in $pD \to ^3He $ reaction$

Abstract

The differential cross sections of $pD\to ^3He X$ reactions, where $X=\eta, \ \eta'\ ,\omega, \ \phi $, are calculated on the basis of a two-step mechanism involving the subprocesses $pp\to d\pi ^+$ and $\pi^+n\to Xp $. It is shown that this model describes well the form of energy dependence of available experimental cross sections at the final c.m.s. momentum $p^*$=0.4-1$ GeV/c$ for the $\eta $ and at $p^*=0-0.5$ GeV/c for the $\omega $ meson as well as the ratios $R(\eta'/\eta) $ and $R(\phi/\omega)$. The absolute value of the cross section is underestimated by an overall normalization factor of about 3 for $\eta, \ \eta '$ and by nearly one order of magnitude for $\omega$ and $\phi$. The spin-spin correlations are predicted for the reaction ${\vec D}{\vec p}\to ^3He X$ in the forward-backward approximations for the elementary amplitudes.