Schematic models for pentaquarks based on diquarks
Edward Shuryak
Stony Brook

Deeply bound diquarks which may be used as building blocks in the formation of multiquark states, in particular pentaquarks and dibaryons. We discuss few simple models in which the lowest scalar diquark (and possibly the tensor one) can be treated as an independent ``body'', with the same color and (approximately) the mass as a constituent (anti)quark. In this model a new symmetry between states with the same number of ``bodies'' but different number of quarks appear, in particular the 3-``body'' pentaquarks can be naturally related to decuplet baryons. We estimate both the masses and widths of such states, and then discuss the limitations of this model. Two scalar diaquarks, as proposed by Jaffe and Wilczek, lead to heavier objects than a sccalar and tensor diquarks. In the latter case the multiplet is 27, not anti-10, which can help to distingush them.