$\bar{p}p$ annihilation into $\bar{D}D$ meson pair within an effective Lagrangian model

Abstract

We study the charmed meson pair (${\bar{D}}^0{D}^0$ and $D^{-}{D}^{+}$) production in $\bar{p}p$ annihilation within an effective Lagrangian model that has only the baryon-meson degrees of freedom and involves the physical hadron masses. The reaction amplitudes include terms corresponding to the t-channel ${\Lambda }_c^{+}$, ${\Sigma }_c^{+}$ and ${\Sigma }_c^{++}$ baryon exchanges and the s-channel excitation, propagation and decay of the $\Psi$(3770) resonance into the charmed mesons. The initial- and final-state distortion effects have been accounted for by using a simple eikonal approximation-based procedure in the same way as was done in our previous study of the $\bar{p}p\to {\bar{\Lambda }}_c^{-}{\Lambda }_c^{+}$ reaction within a similar model. The ${\bar{D}}^0{D}^0$ production reaction is dominated by the ${\Lambda }_c^{+}$ baryon exchange process, and the corresponding total cross sections are predicted to be in the range of 0.18 - 0.7 $\mu$b for antiproton beam momenta varying between threshold and 20 $GeV/c$. The $\Psi$(3770) resonance contributions have a large influence on the differential cross sections of the $D^{-}{D}^{+}$ production reaction.

Comments: 23 pages, 10 figures, Journal Print version