D' DIBARYON IN A COLORED CLUSTER MODEL

The mass and wave function of a six-quark system with quantum numbers J(p)=0(-), T=0, called d', are calculated. We use a colored diquark-te traquark cluster model for the six-quark wave function. A constituent quark model Hamiltonian with a two-body confinement potential, and res idual one-gluon, one-pion, and one-sigma exchange interactions is used . The complications due to the quark exchange interactions between tet raquark and diquark clusters (Pauli principle) are taken into account within the framework of the resonating group method. The calculated d' mass is some 350 MeV above the empirical value if the same two-body c onfinement strength as in the nucleon and Delta is used. This paper al so examines the validity of the usual assumption of a universal two-qu ark confinement strength. We propose that the effective two-body confi nement strength in an exotic six-quark system, such as the d', could b e weaker than in a single baryon. The weaker confinement hypothesis le ads to a d' mass of M-d' = 2092 MeV and a d' radius of r(d') = 1.53 fm .