Color nonsinglet spectroscopy

Study of the spectrum and structure of color nonsinglet combinations of quarks and antiquarks, neutralized by a nondynamical compensating color source, may provide an interesting way to address questions about QCD that cannot be addressed by experiment at the present time. These states can be simulated in lattice QCD and the results can be used to improve phenomenological models of hadrons. Here these ideas are applied to color triplet states of $qqqq$ and $qq\overline{q}$.

Figure 1

$SU(3{)}_f$ diagrams for the $[qq{]}^{3_c}$, $[qqqq{]}^{3_c}$, and $[qq\overline{q}{]}^{3_c}$ states. States with the same isospin and hypercharge mix when $SU(3{)}_f$ violation is turned on if they have the same total angular momentum.

Figure 2

The spectrum of $[qqqq{]}^{3_c}$ states. The first column shows colormagnetic model splittings. The second gives a sketch of the ordering of states in the schematic diquark model. $SU(3{)}_f$ multiplets are labeled by icons of their weight diagrams.

Figure 3

The spectrum of $[qq\overline{q}{]}^{3_c}$ states. The first column shows colormagnetic model splittings. The second gives a sketch of the ordering of states in the schematic diquark model. $SU(3{)}_f$ multiplets are labeled by icons of their weight diagrams.