Dynamics of ${}^1{S}_0$ diproton formation in the $pd\to \{pp{\}}_{s}n$ and $pN\to \{pp{\}}_s\ddot{I}€$ reactions in the GeV region

Abstract

Mechanisms for the production of ${}^1{S}_0$ diproton pairs, ${pp}_s$, in the $pd\to {pp}_{s}n$ reaction are studied at proton beam energies 0.5 -- 2 GeV in kinematics similar to those of backward elastic $pd$ scattering. This reaction provides valuable information on the short-range $NN$ and $pd$ interactions that is complementary to that investigated in the well known $pd\to dp$ and $dp\to p(0^{\circ })X$ processes. The $pd\to {pp}_{s}n$ reaction is related to the subprocesses $\ddot{I}{€}^{0}d\to pn$ and $pN\to {pp}_s\ddot{I}€$ using two different one--pion--exchange (OPE) diagrams. Within both these models a reasonable agreement could be obtained with the data below 1GeV. The similar energy dependence of the $pd\to \{pp{\}}_{s}n$ and $pd\to dp$ cross sections and the small ratio of about 1.5% in the production of $\{pp{\}}_s$ to deuteron final states follow naturally within the OPE models.

10 pages, 7 figures, Latex