Novel six-quark hidden-color dibaryon states in QCD

The recent observation of a hadronic resonance d* in the proton-neutron system with isospin I = 0 and spin-parity J(P) = 3(+) raises the possibility of producing other novel six-quark dibaryon configurations allowed by QCD. A dramatic example of an exotic six-quark color-singlet system is the charge Q = +4, isospin I = 3, I-z = +3 vertical bar uuuuuu > state which couples strongly to Delta(++) + Delta(++). The width and decay properties of such six-quark resonances could be regarded as manifestations of "hidden-color" six-quark configurations, a first-principle prediction of QCD - SU(3)-color gauge theory for the deuteron distribution amplitude. Other implications and possible future experiments are discussed. (C) 2013 Elsevier B.V. All rights reserved.