The spectra and dominant decay couplings of $Q^2{\overline{Q}}^2$ mesons are presented as calculated in the quark-bag model. Certain known $0^{+}$ mesons [$\epsilon \mathrm{}\left(700\right),S^{*},\delta ,\kappa$] are assigned to the lightest cryptoexotic $Q^2{\overline{Q}}^2$ nonet. The usual quark-model $0^{+}$ nonet ($Q\overline{Q} L=1\mathrm{}$) must lie higher in mass. All other $Q^2{\overline{Q}}^2$ mesons are predicted to be broad, heavy, and usually inelastic in formation processes. Other $Q^2{\overline{Q}}^2$ states which may be experimentally prominent are discussed.

• Received 15 July 1976

DOI:https://doi.org/10.1103/PhysRevD.15.267