Charmed-baryon production in antiproton-proton collisions within an effective Lagrangian model

Abstract

We study the productions of charmed baryons ${\bar \Lambda}_c^- \Lambda_c^+$, ${\bar \Lambda}_c^- \Sigma_c^+$, and ${\bar \Sigma}^- \Sigma_c^+$ in the antiproton-proton collisions within an effective Lagrangian model that has only the baryon-meson degrees of freedom and involves the physical hadron masses. The baryon production proceeds via the $t$-channel exchanges of $D^0$ and $D^{*0}$ mesons in the initial collision of the antiproton with the target proton. The distortion effects in the initial and final states are accounted for by using an eikonal approximation-based procedure. We find that the reaction amplitudes of all the production channels are dominated by the $D^{*0}$ meson-exchange diagrams. We discuss the relative roles of tensor and vector components of the $D^{*0}$ coupling in the $D^{*0}$ meson-exchange component of the total production cross sections. The magnitudes of the cross sections are predicted for each final state for the range of beam momenta of relevance to the ${\bar P}ANDA$ experiment.