Oset, E., Chen, H. X., Feijoo, A., Geng, L. S., Liang, W. H., Li, D. M., et al. (2016). Study of reactions disclosing hidden charm pentaquarks with or without strangeness. Nucl. Phys. A, 954, 371–392.
Abstract: We present results for five reactions, Lambda(b) -> J/psi K(-)p, Lambda(b) -> J/psi eta Lambda, Lambda(b) -> J/psi pi(-)p, Lambda(b) -> J/psi K-0 Lambda and Xi(-)(b) -> J/psi K-Lambda, where combining information from the meson baryon interaction, using the chiral unitary approach, and predictions made for molecular states of hidden charm, with or without strangeness, we can evaluate invariant mass distributions for the light meson baryon states, and for those of J/psi p or J/psi Lambda. We show that with the present available information, in all of these reactions one finds peaks where the pentaquark states show up. In the Lambda(b) -> J/psi K(-)p, and Lambda(b) -> J/psi pi(-)p reactions we show that the results obtained from our study are compatible with present experimental observations.
|
Chen, H. X., & Oset, E. (2013). pi pi interaction in the rho channel in finite volume. Phys. Rev. D, 87(1), 016014–15pp.
Abstract: The aim of this paper is to investigate an efficient strategy that allows one to obtain pi pi phase shifts and rho meson properties from QCD lattice data with high precision. For this purpose we evaluate the levels of the pi pi system in the rho channel in finite volume using chiral unitary theory. We investigate the dependence on the pi mass and compare this with other approaches which use QCD lattice calculations and effective theories. We also illustrate the errors induced by using the conventional Luscher approach instead of a more accurate one that was recently developed that takes into account exactly the relativistic two-meson propagators. Finally, we make use of this latter approach to solve the inverse problem, getting pi pi phase shifts from “synthetic” lattice data, providing an optimal strategy and showing which accuracy is needed in these data to obtain the rho properties with a desired accuracy.
|
Geng, L. S., Ren, X. L., Zhou, Y., Chen, H. X., & Oset, E. (2015). S-wave KK* interactions in a finite volume and the f(1)(1285). Phys. Rev. D, 92(1), 014029–9pp.
Abstract: Lattice QCD simulations provide a promising way to disentangle different interpretations of hadronic resonances, which might be of particular relevance to understand the nature of the so-called XYZ particles. Recent studies have shown that in addition to the well-established naive quark model picture, the axial-vector meson f(1)(1285) can also be understood as a dynamically generated state built upon the KK* interaction. In this work, we calculate the energy levels of the KK* system in the f(1)(1285) channel in finite volume using the chiral unitary approach. We propose to calculate the loop function in the dimensional regularization scheme, which is equivalent to the hybrid approach adopted in previous studies. We also study the inverse problem of extracting the bound state information from synthetic lattice QCD data and comment on the difference between our approach and the Luscher method.
|
Lin, J. X., Li, J. T., Liang, W. H., Chen, H. X., & Oset, E. (2024). J/ψ decays into ω(φ) f1(1285) and ω(φ) “f1(1420)”. Eur. Phys. J. C, 84(1), 52–8pp.
Abstract: We perform a theoretical study of the J/psi -> omega (Phi)K* K + c.c. -> omega(Phi)K-0 pi+ K- reactions with the assumption that the f1(1285) is dynamically generated from a single channel K*K + c.c interaction in the chiral unitary approach. Two peaks in the K-0 pi+ K- invariant mass distribution are observed, one clear peak locates at the f(1)(1285) nominal mass, the other peak locates at around 1420MeV with about 70MeV width. We conclude that the former peak is associated with the f(1)(1285) and the latter peak is not a genuine resonance but a manifestation of the kinematic effect in the higher energy region caused by the K* K + c.c. decay mode of the f(1)(1285).
|
Sun, B. X., Chen, H. X., & Oset, E. (2011). rho rho N and rho rho Delta molecules with J(P)=5/2(+) and J(P)=7/2(+). Eur. Phys. J. A, 47(10), 127–8pp.
Abstract: The rho rho N and rho rho Delta three-body systems have been studied within the framework of the fixed center approximation of Faddeev equation. The rho rho interaction in isospin I = 0, spin S = 2 is strongly attractive, and so are the N rho, Delta rho interactions. This leads to bound states of both rho rho N and rho rho Delta. We find peaks of the modulus squared of the scattering matrix around 2227 MeV for rho rho N, and 2372 MeV for rho rho Delta. Yet, the strength of the peak for the rho rho N amplitude is much smaller than for rho rho Delta, weakening the case for a rho rho N bound state, or a dominant rho rho N component. A discussion is made on how these states can be searched for in present programs looking for multimeson final states in different reactions.
|