Bound states of heavyQ22systems

Abstract
The Born-Oppenheimer approximation for heavy quarks in the MIT bag is extended to the Q2Q¯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 c2c¯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.
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