Search for diquark clustering in baryons

In the framework of the nonrelativistic quark model, we examine to what extent baryons consist of a quark bound to a localized cluster of two quarks simulating a diquark. We consider ground states and orbital excitations for various flavor combinations. A striking clustering shows up sometimes especially for the leading Regge trajectory of the nucleon and single-flavored baryons or for the ground state of baryons bearing two heavy flavors. This is, however, far from being a general pattern and there are clear differences between the three-quark description of baryons and the quark-diquark model