Baryonium

TL;DR

This paper investigates the potential for bound states in heavy baryon-antibaryon systems using heavy baryon perturbation theory with two-pion exchange, calculating scattering properties and exploring binding conditions for various systems.

Contribution

It provides a detailed analysis of heavy baryon-antibaryon interactions, deriving potentials, and assessing the possibility of bound states, including the impact of coupling constants and extending to bottom baryons.

Findings

Lambda_c-anti-Lambda_c can be bound with a sufficiently large coupling constant.

Scattering phase shifts and lengths are calculated for specific baryon pairs.

Binding energies are estimated for systems that can form bound states.

Abstract

In the framework of the heavy baryon perturbation theory, in which the two-pion exchange is considered, the physical properties of heavy-baryon-anti-heavy-baryon systems are revisited. The potentials between heavy-baryon and anti-heavy-baryon are extracted in a holonomic form. Based on the extracted potentials, the s-wave scattering phase shifts and scattering lengths of $\Lambda_c$-$\bar{\Lambda}_c$ and $\Sigma_c$-$\bar{\Sigma}_c$ are calculated. From these scattering features, it is found that the $\Lambda_c$-$\bar{\Lambda}_c$ system can be bound only when the value of the coupling constant $g_2$ is larger than that from the decay data of the $\Sigma_c(\Sigma_c^*) \to \Lambda_c \pi$ process. The binding condition for the $\Sigma_c$-$\bar{\Sigma}_c$ system is also examined. The binding possibilities of these systems deduced from the scattering calculations are also checked by the bound state calculation and the binding energies are obtained if the system can be really bound. The binding possibility of the $\Lambda_b$-$\bar{\Lambda}_b$ system is investigated as well.