2015/10/31 by Ruilin Zhu, Cong‐Feng Qiao, Cong-Feng Qiao · 7 citations
Physics and Astronomy · #Diquark #Hadron #Hamiltonian (control theory) #High-Energy Particle Collisions Research #Nuclear physics #Particle physics #Particle physics theoretical and experimental studies #Pentaquark #Physics #Quantum Chromodynamics and Particle Interactions #Tetraquark #hep-ex #hep-ph #nucl-ex
paper · pdf · doi:10.1016/j.physletb.2016.03.022
published as Phys. Lett. B756, 259 (2016) · 7 pages, 3 figures, 1 table; matches the version accepted in Phys.Lett.B
arxiv created 2016/03/08 · openalex publication_date 2016/03/10 · arxiv updated 2016/03/24 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
The diquark–triquark model is used to explain charmonium-pentaquark states, i.e., Pc(4380) and Pc(4450), which were observed recently by the LHCb Collaboration. For the first time, we investigate the properties of the color attractive configuration of a triquark and we define a nonlocal light cone distribution amplitude for pentaquark states, where both diquark and triquark are not pointlike, but they have nonzero size. We establish an effective diquark–triquark Hamiltonian based on spin–orbital interaction. According to the Hamiltonian, we show that the minimum mass splitting between 52+ and 32− is around 100 MeV, which may naturally solve the challenging problem of small mass splitting between Pc(4450) and Pc(4380). This helps to understand the peculiarities of Pc(4380) with a broad decay width whereas Pc(4450) has a narrow decay width. Based on the diquark–triquark model, we predict more pentaquark states, which will hopefully be measured in future experiments.