Variational fit to the lattice energy of two heavy-light mesons

Recent lattice calculations on the interaction energy of two heavy-light mesons ${(Q}^2{q}^2)$ in SU(3) are interpreted in terms of the potential for the corresponding single heavy-light meson $\left(Q\overline{q}\right).\mathrm{}$ This model supports earlier work, with four static quarks $Q^4$ in SU(2), that there is a large overestimate of the binding compared with the lattice data—unless the basic $Q\overline{q}$ potentials are modified by a four-quark form factor.