Supposing quarkdiquark structure of baryons, we look for systematics of baryons composed of light quarks (q = u, d). We systematize baryons using the notion of two diquarks: (i) axialvector state, D1 1, with the spin SD = 1 and isospin ID = 1 and (ii) scalar one, D 0 0, with the spin SD = 0 and isospin ID = 0. We consider several schemes for the composed baryons: (1) with different diquark masses, M D 0 0 ≠ M D 11, (2) with M D00 = M D 11 and overlapping q D00 and qD11 states (resonances), (3) with/without SU(6) constraints for low-lying states (with quarkdiquark orbital momenta L = 0). In the high-mass region, the model predicts several baryon resonances at M ∼ 2.02.9 GeV. Moreover, the model gives us the double pole structure (i.e. two poles with the same Re M but different Im M) in many amplitudes at masses M ≳ 2.0 GeV. We see also that for description of low-lying baryons (with L = 0), the SU(6) constraint is needed.
- Quark model
ASJC Scopus subject areas
- Atomic and Molecular Physics, and Optics
- Nuclear and High Energy Physics
- Astronomy and Astrophysics