Techniques for estimating the masses and decay couplings of multiquark hadrons ($Q^m{\overline{Q}}^n$, $n+m>\mathrm{}3\mathrm{}$) are developed with specific reference to the $Q^2{\overline{Q}}^2$ sector. The dynamics is based on a quark-bag model of light, colored, and permanently confined quarks gauge-coupled to non-Abelian colored gluons. The SU (6) of "color-spin" generated by color SU (3) and the SU (2) of relativistic $j=\frac{1}{2}$ quarks dominates the spectrum. Color-spin rules analogous to Hund's rules of atomic spectroscopy dictate that the lightest multiquark handrons are not exotic, are of low spin, and are coupled predominantly to strange $Q^3$ and $Q\overline{Q}$ decay channels, Multiquark hadrons are consequently elusive and may be misclassified as conventional $Q\overline{Q}$ mesons or $Q^3$ baryons.

• Received 15 July 1976

DOI:https://doi.org/10.1103/PhysRevD.15.281