PIONIC DECAY OF A POSSIBLE D' DIBARYON AND THE SHORT-RANGE NN INTERACTION

We study the pionic decay of a possible dibaryon d'-->N+ N+ pi in the microscopic quark shell model. The initial d' dibaryon wave function ( J(P)=0(-), T=0) consists of one 1 (h) over bar omega six-quark shell-m odel s(5)p[51](x) configuration. The most important final six-quark co nfigurations s(6)[6](x), s(4)p(2)[42](x), and (s(4)p(2)-s(5)2s)[6](x) an properly projected onto the NN channel. The final state NN interact ion is investigated by means of two phase-equivalent-hut off-shell dif ferent-potential models. We demonstrate that the decay width Gamma(d') depends strongly on the short-range behavior of the NN wave function. In addition, the width Gamma(d') is very sensitive to the mass and si ze of the d' dibaryon. For dibaryon masses slightly above the experime ntally suggested value M-d'=2.065 GeV, we obtain a pionic decay width of Gamma(d')approximate to 0.18-0.32 MeV close to the experimental val ue Gamma(d')approximate to 0.5 MeV.