
Dai, L. R., Toledo, G., & Oset, E. (2020). Searching for a D(D)overbar bound state with the psi(3770) > gamma D0(D)overbar(0) decay. Eur. Phys. J. C, 80(6), 510–8pp.
Abstract: We perform a calculation of the mass distribution in the psi(3770) > gamma D (D) over bar decay, studying both the D+D and D0(D) over bar (0) decays. The electromagnetic interaction is such that the tree level amplitude is null for the neutral channel, which forces the psi(3770) > gamma D0(D) over bar (0) transition to go through a loop involving the D+D > D0(D) over bar (0) scattering amplitude. We take the results for this amplitude from a theoretical model that predicts a D (D) over bar bound state and find a D0(D) over bar (0) mass distribution in the decay drastically different than phase space. The rates obtained are relatively large and the experiment is easily feasible in the present BESIII facility. The performance of this experiment could provide an answer to the issue of this much searched for state, which is the analogue of the f(0)(980) resonance.



Dias, J. M., Toledo, G., Roca, L., & Oset, E. (2021). Unveiling the K1(1270) doublepole structure in the (B)overbar > J/psi rho(K)overbar and (B)overbar > J/psi(K)overbar*pi decays. Phys. Rev. D, 103(11), 116019–13pp.
Abstract: By looking at the pseudoscalarvector meson spectra in the (B) over bar > J/psi rho(K) over bar and (B) over bar > J/psi(K) over bar*pi weak decays, we theoretically investigate the doublepole structure of the K1 (1270) resonance by using the chiral unitary approach to account for the finalstate interactions between the pseudoscalar (P) and vector (V) mesons. The K1 (1270) resonance is dynamically generated through these interactions in coupled channels and influences the shape of the invariant mass distributions under consideration. We show how these shapes are affected by the K1 (1270) doublepole structure to confront the results from our model with future experiments that might investigate the PV spectra in these decays.



Ikeno, N., Liang, W. H., Toledo, G., & Oset, E. (2022). Interpretation of the Omega(c) > pi(+) Omega(2012) > pi(+) ((K)overbar Xi) relative to Omega(c) > pi(+) (K)overbar Xi from the Omega (2012) molecular perspective. Phys. Rev. D, 106(3), 034022–10pp.
Abstract: We present a mechanism for Omega(c) > pi(+)Omega (2012) production through an external emission Cabibbo favored weak decay mode, where the Omega (2012) is dynamically generated from the interaction of (K) over bar Xi(*) (1530) and eta Omega, with (K) over bar Xi as the main decay channel. The Omega (2012) decays later to (K) over bar Xi. in this picture, with results compatible with Belle data. As a consequence, one can evaluate the direct decay Omega(0)(c) > pi K+()Xi(0) and the decay Omega(0)(c) > pi(+)(K) over bar Xi* pi(+)eta Omega with direct couplings of (K) over bar Xi* and eta Omega to KXi(0). We show that, within uncertainties and using data from a recent Belle measurement, all three channels account for about (1220)% of the total Omega(c) > pi K+()Xi(0) decay rate. The consistency of the molecular picture with all the data is established by showing that Omega(c) > Xi(0)(K) over bar*(0) > Xi K0()pi(+) and Omega(c) > pi(+)Omega* > pi K+(Xi 0) account for about 85% of the total Omega(c) > pi K+()Xi(0).



Ikeno, N., Toledo, G., Liang, W. H., & Oset, E. (2023). Consistency of the Molecular Picture of Omega(2012) with the Latest Belle Results. FewBody Syst., 64(3), 55–6pp.
Abstract: We report the results of the research on the Omega(2012) state based on themolecular picture and discuss the consistency of the picture with the Belle experimental results. We study the interaction of the (K) over bar Xi*, eta Omega(swave) and (K) over bar Xi(dwave) channels within a coupled channel unitary approach, and obtain the mass and the width of the Omega(2012) state and the decay ratio RXi(K) over bar(Xi pi(K) over bar). We also present a mechanism for Omega c > pi(+)Omega(2012) production through an external emission Cabibbo favoredweak decay mode, where the Omega(2012) is dynamically generated from the above interaction. We find that the results obtained by the molecular picture are consistent with all Belle experimental data.



Ikeno, N., Toledo, G., & Oset, E. (2023). Model independent analysis of femtoscopic correlation functions: An application to the D∗s0(2317). Phys. Lett. B, 847, 138281–6pp.
Abstract: We face the inverse problem of obtaining the interaction between coupled channels from the correlation functions of these channels. We apply the method to the interaction of the (DK+)K0, (D+K0), and Ds(+)eta channels, from where the Ds0(& lowast;)(2317) state emerges. We use synthetic data extracted from an interaction model based on the local hidden gauge approach and find that the inverse problem can determine the existence of a bound state of the system with a precision of about 20 MeV. At the same time, we can determine the isospin nature of the bound state and its compositeness in terms of the channels. Furthermore, we evaluate the scattering length and effective range of all three channels, as well as the couplings of the bound state found to all the components. Lastly, the size parameter of the source function, R, which in principle should be a magnitude provided by the experimental teams, can be obtained from a fit to the data with relatively high accuracy. These findings show the value of the correlation function to learn about the mesonmeson interaction for systems which are difficult to access in other present facilities.



Ikeno, N., Toledo, G., & Oset, E. (2020). Molecular picture for the Omega(2012) revisited. Phys. Rev. D, 101(9), 094016–9pp.
Abstract: We conduct a study of the interaction of the (K) over bar Xi*, eta Omega(swave), and (K) over bar Xi(dwave) channels within a coupled channel unitary approach where the transition potential between the (K) over bar Xi* and eta Omega channels is obtained from chiral Lagrangians. The transition potential between (K) over bar Xi*, eta Omega, and (K) over bar Xi is taken in terms of free parameters, which together with a cutoff to regularize the mesonbaryon loops are fitted to the Omega(2012) data. We find that all data including the recent Belle experiment on Gamma(Omega*>pi(K) over bar Xi)/Gamma(Omega*>(K) over bar Xi), are compatible with the molecular picture stemming from meson baryon interaction of these channels.



Sakai, S., Liang, W. H., Toledo, G., & Oset, E. (2020). J/psi > gamma pi pi, gamma pi(0)eta reactions and the f(0)(980) and a(0)(980) resonances. Phys. Rev. D, 101(1), 014005–9pp.
Abstract: We study the J/psi > gamma pi(+)pi(), gamma pi(0)eta reactions from the perspective that they come from the J/psi > phi(omega)pi(+)pi(), rho(0)pi(0)eta reactions, where the rho(0), psi, and phi get converted into a photon via vector meson dominance. Using models successfully used previously to study the J/psi > omega(phi)pi pi reactions, we make determinations of the invariant mass distributions for pi(+)pi() in the regions of the f(0)(500), f(0)(980), and for pi(0)eta in the region of the a(0)(980). The integrated differential widths lead to branching ratios below present upper bounds, but they are sufficiently large for future check in updated facilities.



Toledo, G., Ikeno, N., & Oset, E. (2021). Theoretical study of the D0 > Kpi(+)eta reaction. Eur. Phys. J. C, 81(3), 268–11pp.
Abstract: We develop a model to study the D0 > Kpi(+)eta weak decay, starting with the color favored external emission and Cabibbo favored mode at the quark level. A less favored internal emission decay mode is also studied as a source of small corrections. Some pairs of quarks are allowed to hadronize producing two pseudoscalar mesons, which posteriorly are allowed to interact to finally provide the Kpi(+)eta state. The chiral unitary approach is used to take into account the final state interaction of pairs of mesons, which has as a consequence the production of the kappa (K0*(700)) and the a(0)(980) resonances, well visible in the invariant mass distributions. We also introduce the (K) over bar*(0)eta production in a phenomenological way and show that the swave pseudoscalar interaction together with this vector excitation mode are sufficient to provide a fair reproduction of the experimental data. The model provides the relative weight of the a(0)(980) to the kappa excitation, and their strength is clearly visible in the low energy part of the K pi spectrum.

