, 72:2204,
Open Access This content is freely available online to anyone, anywhere at any time.
Date: 31 Oct 2012

The “closed” chiral symmetry and its application to tetraquark


We investigate the chiral (flavor) structure of tetraquarks, and study chiral transformation properties of the “non-exotic” \([(\bar{\mathbf{3}}, \mathbf{3})\oplus(\mathbf{3}, \bar{\mathbf{3}})]\) and [(8,1)⊕(1,8)] tetraquark chiral multiplets. We find that as long as this kind of tetraquark states contains one quark and one antiquark having the same chirality, such as \(q_{L} q_{L} \bar{q}_{L} \bar{q}_{R} + q_{R} q_{R} \bar{q}_{R} \bar{q}_{L}\), they transform in the same way as the lowest level \(\bar{q} q\) chiral multiplets under chiral transformations. There is only one \([(\bar{\mathbf{3}}, \mathbf{3})\oplus (\mathbf{3}, \bar{\mathbf{3}})]\) chiral multiplet whose quark-antiquark pairs all have the opposite chirality (\(q_{L} q_{L} \bar{q}_{R} \bar{q}_{R} + q_{R} q_{R} \bar{q}_{L} \bar{q}_{L}\)), and it transforms differently from others. Based on these studies, we construct local tetraquark currents belonging to the “non-exotic” chiral multiplet \([(\bar{\mathbf{3}}, \mathbf{3})\oplus(\mathbf{3}, \bar{\mathbf{3}})]\) and having quantum numbers J PC =1−+.