|
|
Dias, J. M., Debastiani, V. R., Xie, J. J., & Oset, E. (2018). The radiative decay D-0 -> (K)over-bar*(0)gamma with vector meson dominance. Chin. Phys. C, 42(4), 043106–7pp.
Abstract: Motivated by the experimental measurements of D-0 radiative decay modes, we have proposed a model to study the D-0 -> (K) over bar*(0)gamma decay, by establishing a link with D-0 -> (K) over bar*(0) V (V = rho(0), omega) decays through the vector meson dominance hypothesis. In order to do this properly, we have used the Lagrangians from the local hidden gauge symmetry approach to account for V gamma conversion. As a result, we have found the branching ratio B[D-0 -> (K) over bar*(0)gamma]=(1.55-3.44)x10(-4), which is in fair agreement with the experimental values reported by the Belle and BaBar collaborations.
|
|
|
|
Dias, J. M., Yu, Q. X., Liang, W. H., Sun, Z. F., Xie, J. J., & Oset, E. (2020). Xi(bb) and Omega(bbb) molecular states. Chin. Phys. C, 44(6), 064101–8pp.
Abstract: Using the vector exchange interaction in the local hidden gauge approach, which in the light quark sector generates the chiral Lagrangians and has produced realistic results for Omega(C), Xi(c), Xi(b) and the hidden charm pentaquark states, we study the meson-baryon interactions in the coupled channels that lead to the Xi(bb) and Omega(bbb) excited states of the molecular type. We obtain seven states of the Xi(bb) type with energies between and MeV, and one Omega(bbb) state at MeV.
|
|
|
|
Aceti, F., Bayar, M., Dias, J. M., & Oset, E. (2014). Prediction of a Z(c)(4000) state and relationship with the claimed Z(c)(4025). Eur. Phys. J. A, 50(6), 103–13pp.
Abstract: After discussing the OZI suppression of one light meson exchange in the interaction of with isospin I = 1 , we study the contribution of the two-pion exchange to the interaction and the exchange of heavy vectors, J/psi for diagonal transitions and D-* for transitions of to J/psi rho. We find these latter mechanisms to be weak, but enough to barely bind the system in J = 2 with a mass around 4000 MeV, while the effect of the two-pion exchange is a net attraction, though weaker than that from heavy-vector exchange. We discuss this state and try to relate it to the Z (c) (4025) state, above the threshold, claimed in an experiment at BES from an enhancement of the distribution close to threshold. Together with the results from a recent reanalysis of the BES experiment showing that it is compatible with a J = 2 state below threshold around 3990 MeV, we conclude that the BES experiment could show the existence of the state that we find in our approach.
|
|
|
|
Aceti, F., Dias, J. M., & Oset, E. (2015). f(1)(1285) decays into a(0)(980) pi(0), f(0)(980) pi(0) and isospin breaking. Eur. Phys. J. A, 51(4), 48–8pp.
Abstract: We evaluate the decay width for the processes f1(1285). p 0 a0(980) and f1(1285). p 0 f0(980) taking into account that all three resonances are dynamically generated from the meson- meson interaction, the f1(1285) from K* K – c. c. and the a0(980), f0(980) from p., K K and pp, K _ K, respectively. We use a triangular mechanism similar to that of.(1405). pp., which provides a decay width for f1(1285). p 0 a0(980) with a branching fraction of the order of 30%, in agreement with experiment. At the same time we evaluate the decay width for the isospin- forbidden f1(1285). p 0 f0(980), which appears when we consider different masses for the charged and neutral kaons, and show that it is much more suppressed than in the.(1405). pp. case, but gives rise to a narrow shape of the p + p- distribution similar to the one found in the eta(1405) -> pi pi eta decay.
|
|
|
|
Dai, L. R., Dias, J. M., & Oset, E. (2018). Disclosing D* (D)over bar* molecular states in the B-c(-) -> pi(-) J/psi omega decay. Eur. Phys. J. C, 78(3), 210–7pp.
Abstract: We study the B-c(-) -> pi(-) J/omega and B-c(-) -> pi(-) D* (D) over bar* reactions and show that they are related by the presence of two resonances, the X(3940) and X(3930), that are of molecular nature and couple most strongly to D* (D) over bar*, but also to J/psi omega. Because of that, in the J/psi omega mass distribution we find a cusp with large strength at the D* (D) over bar* threshold and predict the ratio of strengths between the peak of the cusp and the maximum of the D* (D) over bar* distribution close to D* (D) over bar* threshold, which are distinct features of the molecular nature of these two resonances.
|
|
|
|
Yu, Q. X., Dias, J. M., Liang, W. H., & Oset, E. (2019). Molecular Xi(bc) states from meson-baryon interaction. Eur. Phys. J. C, 79(12), 1025–13pp.
Abstract: We have studied the meson-baryon interaction in coupled channels with the same quantum numbers of Xi bc. The interaction is attractive in some channels and of sufficient intensity to lead to bound states or resonances. We use a model describing the meson-baryon interaction based on an extrapolation of the local hidden gauge approach to the heavy sector, which has been successfully used in predicting omega c and hidden charm states. We obtain many states, some of them narrow or with zero width, as a consequence of the interaction, which qualify as molecular states in those channels. The success in related sectors of the picture used should encourage the experimental search for such states.
|
|
|
|
Liang, W. H., Dias, J. M., Debastiani, V. R., & Oset, E. (2018). Molecular Omega(b) states. Nucl. Phys. B, 930, 524–532.
Abstract: Motivated by the recent finding of five Omega(c) states by the LHCb collaboration, and the successful reproduction of three of them in a recent approach searching for molecular states of meson-baryon with the quantum numbers of Omega(c), we extend these ideas and make predictions for the interaction of meson-baryon in the beauty sector, searching for poles in the scattering matrix that correspond to physical states. We find several Omega(b) states: two states with masses 6405 MeV and 6465 MeV for J(P) = 1/2(-) ; two more states with masses 6427 MeV and 6665 MeV for 3/4(-) ; and three states between 6500 and 6820 MeV, degenerate with J(P) = 1/2(-), 3/4(-), stemming from the interaction of vector-baryon in the beauty sector.
|
|
|
|
Aceti, F., Bayar, M., Oset, E., Martinez Torres, A., Khemchandani, K. P., Dias, J. M., et al. (2014). Prediction of an I=1 D(D)over-bar* state and relationship to the claimed Z(c)(3900), Z(c)(3885). Phys. Rev. D, 90(1), 016003–13pp.
Abstract: We study here the interaction of D (D) over bar* in the isospin I = 1 channel in light of recent theoretical advances that allow us to combine elements of the local hidden gauge approach with heavy quark spin symmetry. We find that the exchange of light q (q) over bar is Okubo-Zweig-Iizuka (OZI) suppressed and thus we concentrate on the exchange of heavy vectors and of two pion exchange. The latter is found to be small compared to the exchange of heavy vectors, which then determines the strength of the interaction. A barely D (D) over bar* bound state decaying into eta(c)rho and pi J/psi is found. At the same time we reanalyze the data of the BESIII experiment on e(+)e(-) -> pi(+/-)(D (D) over bar*)(-/+), from where a Z(c)(3885) state was claimed, associated to a peak in the (D (D) over bar*)(-/+) invariant mass distribution close to threshold, and we find the data compatible with a resonance with mass around 3875 MeV and width around 30 MeV. We discuss the possibility that this and the Z(c)(3900) state found at BESIII, reconfirmed at 3894 MeV at Belle, or 3885 MeV at CLEO, could all be the same state and correspond to the one that we find theoretically.
|
|
|
|
Dias, J. M., Aceti, F., & Oset, E. (2015). Study of B<(B)over bar>* and B*<(B)over bar>* interactions in I=1 and relationship to the Z(b)(10610), Z(b)(10650) states. Phys. Rev. D, 91(7), 076001–14pp.
Abstract: We use the local hidden gauge approach in order to study the B (B) over bar* and B*(B) over bar* interactions for isospin I = 1. We show that both interactions via one light meson exchange are not allowed by the Okubo-ZweigIizuka rule and, for that reason, we calculate the contributions due to the exchange of two pions, interacting and noninteracting among themselves, and also due to the heavy vector mesons. Then, to compare all these contributions, we use the potential related to the heavy vector exchange as an effective potential corrected by a factor which takes into account the contribution of the other light meson exchanges. In order to look for poles, this effective potential is used as the kernel of the Bethe-Salpeter equation. As a result, for the B (B) over bar* interaction we find a loosely bound state with mass in the range 10587-10601 MeV, very close to the experimental value of the Z(b)(10610) reported by the Belle Collaboration. For the B*(B) over bar* case, we find a cusp at 10650 MeV for all spin J = 0, 1, 2 cases.
|
|
|
|
Dias, J. M., Navarra, F. S., Nielsen, M., & Oset, E. (2016). f(0)(980) production in D-s(+)-> pi(+) pi(+) pi(-) and D-s(+) -> pi(+) K+ K- decays. Phys. Rev. D, 94(9), 096002–8pp.
Abstract: We study the D-s(+)-> pi(+) pi(+) pi(-) and D-s(+) -> pi(+) K+ K- decays adopting a mechanism in which the D-s(+) meson decays weakly into a pi+ and a q (q) over bar component, which hadronizes into two pseudoscalar mesons. The final state interaction between these two pseudoscalar mesons is taken into account by using the chiral unitary approach in coupled channels, which gives rise to the f(0)(980) resonance. Hence, we obtain the invariant mass distributions of the pairs pi(+) pi(-) and K+ K- after the decay of that resonance and compare our theoretical amplitudes with those available from the experimental data. Our results are in a fair agreement with the shape of these data, within large experimental uncertainty, and a f(0)(980) signal is seen in both the pi(+) pi(-) and K+ K- distributions. Predictions for the relative size of pi(+) pi(-) and K+ K- distributions are made.
|
|
