We study the ND system by means of a chiral constituent quark model. This model, tuned in the description of the baryon and meson spectra as well as the N N interaction, provides parameter-free predictions for the charm −1 two-hadron systems. The presence of a heavy antiquark makes the interaction rather simple. We have found sharp quark-Pauli effects in some particular channels, generating repulsion, due to lacking degrees of freedom to accommodate the light quarks. Our results point to the existence of an attractive state, the ∆D * with (T, S) = (1, 5/2), presenting a resonance close to threshold. It would show up in the scattering ofD mesons on nucleons as a D wave state with quantum numbers (T )J P = (1)5/2 − . This resonance resembles our findings in the ∆∆ system, that offered a plausible explanation to the cross section of double-pionic fusion reactions through the so-called ABC effect. The study of the interaction of D mesons with nucleons is a goal of thePANDA Collaboration at the European facility FAIR and, thus, the present theoretical study is a challenge to be tested at the future experiments.

No abstract

We study the two-baryon system with two units of charm looking for the possible existence of a loosely bound state resembling the $H$ dibaryon. We make use of a chiral constituent quark model tuned in the description of the baryon and meson spectra as well as the $NN$ interaction. The presence of the heavy quarks makes the interaction simpler than in light baryon systems. We analyze possible quark-Pauli effects that would be present in spin-isospin saturated channels. Our results point to the non-existence of a charmed $H$-like dibaryon, although it may appear as a resonance above the $\Lambda_c\Lambda_c$ threshold.Comment: 13 pages, 6 figures. To appear in Phys. Rev. D. arXiv admin note: text overlap with arXiv:1204.5502, arXiv:1507.0804

By solving exact three-body equations, we study the three-baryon system with charm +1. We look for possible bound states using baryon-baryon interactions obtained from a chiral constituent quark model. The smaller effect of the Λ c ↔ Σ c conversion reverses the order of the (I, J) = (0, 1/2) and (I, J) = (0, 3/2) states, rather close on the strange sector. The diminishing of the kinetic energy due to the large reduced mass gives rise to a bound state in the (I, J) = (0, 3/2) channel. After correcting for Coulomb effects the binding energy would be between 140 and 715 keV.

No abstract