Diquark model of dibaryons

Abstract

A diquark model previously formulated to describe exotic mesons is extended to dibaryons. In the model, dibaryons containing only light quarks are unbound. The $H$ dibaryon, consisting of $uuddss$ quarks, is unstable by about 90 MeV or more, and should decay strongly into two $\Lambda$ baryons. A charmed dibaryon $H_c$, composed of $uuddsc$, is unstable by about 60 MeV or more and should decay strongly into $\Lambda + \Lambda_c$. On the other hand, we find that a bottom dibaryon $H_b$, made of $uuddsb$, may be just bound by about 10 MeV with respect to $\Lambda + \Lambda_b$. If so, it should decay weakly into various final states with a charmed hadron. A possible two-body decay would be into $\Lambda + \Lambda_c$.