The Born-Oppenheimer approximation for heavy quarks in the MIT bag is extended to the $Q^2$Q${¯}^2$ system, where the glue plus volume energy becomes an operator in color space. Taking its lowest eigenvalue as the approximate potential energy, the four-body Schrödinger equation is solved variationally for the ground-state energy. With this approximation, it is found that heavy-quark systems such as $c^2$c${¯}^2$ are stable against breakup into two ψ (cc¯) mesons. It is necessary to solve the coupled-channel (in color space) problem to confirm this result.

• Received 5 December 1984

DOI:https://doi.org/10.1103/PhysRevD.32.755