Exclusive $\bar{\Xi }\Xi$ and ${\bar{\Xi }}_c{\Xi }_c$ production in $\bar{p}p$ collisions at $\sqrt{s}\le 15$ GeV

Abstract

Estimates of differential cross sections and longitudinal asymmetries are presented for the reactions $\bar{p}p\to \bar{\Xi }\Xi$ and $\bar{p}p\to {\bar{\Xi }}_c{\Xi }_c$ at energies $\sqrt{s}\lesssim 15$ GeV. The $\Xi$ and ${\Xi }_c$ hyperons are assumed to be produced in two-step processes: first, intermediate $\bar{\Lambda }\Lambda$ and/or ${\bar{\Lambda }}_c{\Lambda }_c$ states are created which are converted afterwards into final states $\bar{\Xi }\Xi$, ${\bar{\Xi }}_c{\Xi }_c$ and ${\bar{\Xi }}_c{\Xi }_c$. The full amplitudes are described by loop diagrams within a modified Regge model, based on the topological decomposition of planar quark diagrams. A strong sensitivity of the ratio of yields of ${\bar{\Xi }}_c{\Xi }_c$ to $\bar{\Xi }\Xi$ and of ${\bar{\Lambda }}_c{\Lambda }_c$ to $\bar{\Lambda }\Lambda$ to the degree of SU(4) symmetry violation is found.

Comments: 4 pages, 7 figures